Hoover Dam, Southern California Edison 138-KV Switchyard, U.S. Highway...
Significance: It was the second of six major Federal switchyards built at Hoover Dam. The switchyard was built to replace the Southern Sierras Power Company substation that had provided electricity for construc... More
Boulder Farm, Dunbarton Road, Hopkinton, Merrimack County, NH
Survey number: HABS NH-42 Building/structure dates: 1816 Initial Construction
Hoover Dam, Cable Hoist House, U.S. Highway 93, Boulder City, Clark Co...
Significance: It provided access to control cable tunnels from the power plant to the switchyard relay house, and a transformer in the lower level of the hoist house provided operating electricity to the switch... More
Hoover Dam, Cable Hoist House, U.S. Highway 93, Boulder City, Clark Co...
Significance: It provided access to control cable tunnels from the power plant to the switchyard relay house, and a transformer in the lower level of the hoist house provided operating electricity to the switch... More
Hoover Dam, Los Angeles Bureau of Power & Light Lines 1-3, U.S. Highwa...
Significance: The transmission lines included pioneering technology in high-voltage transmission. The lines were crucial elements of the Hoover Dam electrical complex, particularly in the role played by Hoover ... More
Hoover Dam, Metropolitan Water District Switchyard, U.S. Highway 93, B...
Significance: It was the second-largest Federal switchyard at Hoover Dam, the switchyard provided needed power for expansion of irrigation and municipal water supplies in California during and after WWII, but i... More
Hoover Dam, Metropolitan Water District Switchyard, U.S. Highway 93, B...
Significance: It was the second-largest Federal switchyard at Hoover Dam, the switchyard provided needed power for expansion of irrigation and municipal water supplies in California during and after WWII, but i... More
Hoover Dam, Metropolitan Water District Switchyard, U.S. Highway 93, B...
Significance: It was the second-largest Federal switchyard at Hoover Dam, the switchyard provided needed power for expansion of irrigation and municipal water supplies in California during and after WWII, but i... More
Bureau of Mines Boulder City Experimental Station, Administration Offi...
Significance: Building 100, as part of the Date Street Complex, was part of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Boulder City... More
Hoover Dam, U.S. Highway 93 Arizona Segment, U.S. Highway 93, Boulder ...
Public domain photograph - historical image of Arizona, United States, free to use, no copyright restrictions image - Picryl description
Grand Canyon National Park Roads, Boulder Street Headwall No. 1, North...
Significance: This headwall is representative of rustic style road structures constructed by the Civilian Conservation Corps and other depression-era public works agencies within the western national parks duri... More
Hoover Dam, Southern California Edison 230-KV Switchyard, U.S. Highway...
Significance: It was an integral element of the Hoover Dam electrical generation and transmission system. This switchyard provided much-needed electricity during WWII to power Douglas, Vultee, and Northrup airc... More
Hoover Dam, Los Angeles Switch Yard, U.S. Highway 93, Boulder City, Cl...
Significance: It was the first and largest of the six major Federal switchyards at Hoover Dam. When the first stage of the switchyard began operations in 1936, it provided electricity at the highest voltages ev... More
Hoover Dam, Metropolitan Water District Line 1, U.S. Highway 93, Bould...
Significance: The transmission line was a critical element of the Hoover Dam electrical generation and transmission system. The line provided Hoover Dam power for development of irrigation and municipal water d... More
Hoover Dam, Metropolitan Water District Line 1, U.S. Highway 93, Bould...
Significance: The transmission line was a critical element of the Hoover Dam electrical generation and transmission system. The line provided Hoover Dam power for development of irrigation and municipal water d... More
Bureau of Mines Metallurgical Research Laboratory, Original Building, ...
Significance: Building 200, as part of the Date Street Complex, was part of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Boulder City... More
Bureau of Mines Metallurgical Research Laboratory, Original Building, ...
Significance: Building 200, as part of the Date Street Complex, was part of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Boulder City... More
Bureau of Mines Metallurgical Research Laboratory, Original Building, ...
Significance: Building 200, as part of the Date Street Complex, was part of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Boulder City... More
![[Falls in North Boulder Canon] - stereoscopic view, public domain photorpaph](https://cache.getarchive.net/Prod/thumb/cdn4/L3Bob3RvLzIwMTkvMDkvMjcvZmFsbHMtaW4tbm9ydGgtYm91bGRlci1jYW5vbi02NmVmOTMtMTAyNC5qcGc%3D/40/23/webp "[Falls in North Boulder Canon] - stereoscopic view, public domain photorpaph")
[Falls in North Boulder Canon] - stereoscopic view, public domain phot...
Part of series: Beauties of the Rocky Mountains. The albumen silver print is a photographic printing process that was widely used in the 19th century. It involves coating paper support with a mixture of egg w... More
Hoover Dam, Circuits 1-15, U.S. Highway 93, Boulder City, Clark County...
Significance: Transformer Circuits are integral elements of the Hoover Dam electrical generation and transmission system. The circuits contributed to the importance of Hoover Dam power in the WWII and post-war ... More
Hoover Dam, Circuits 1-15, U.S. Highway 93, Boulder City, Clark County...
Significance: Transformer Circuits are integral elements of the Hoover Dam electrical generation and transmission system. The circuits contributed to the importance of Hoover Dam power in the WWII and post-war ... More
Hoover Dam, Circuits 1-15, U.S. Highway 93, Boulder City, Clark County...
Significance: Transformer Circuits are integral elements of the Hoover Dam electrical generation and transmission system. The circuits contributed to the importance of Hoover Dam power in the WWII and post-war ... More
Boulder, Colorado view, photochrome print postcard.
Copyright 1900 by Detroit Photographic Co. Title on inventory list: Boulder. Detroit Publishing Co. no. "50404". Forms part of: Photochrom Print Collection. More information about the Photochrom Print Collecti... More
![[Men seated on rocks overlooking Catskill Mountains: boulder on South Mountain]](https://cache.getarchive.net/Prod/thumb/cdn4/L3Bob3RvLzE5MDIvMDEvMDEvbWVuLXNlYXRlZC1vbi1yb2Nrcy1vdmVybG9va2luZy1jYXRza2lsbC1tb3VudGFpbnMtYm91bGRlci1vbi1zb3V0aC1tb3VudGFpbi02NDAuanBn/40/49/webp "[Men seated on rocks overlooking Catskill Mountains: boulder on South Mountain]")
[Men seated on rocks overlooking Catskill Mountains: boulder on South ...
Photo by A. Loeffler. This record contains unverified, old data from caption card.
Las Vegas, Nevada. A mass of transmission towers and transformers redi...
Picryl description: Public domain image of a construction site, industrial or commercial building, free to use, no copyright restrictions.
Lake Mead National Recreation Area, created by the building of Boulder...
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Title, date, and keywords based on information provided... More
Aerial view of Boulder Dam with Lake Mead in the background Image. Bou...
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Photograph taken in 2001. Title, date, subject note, an... More
A raging stream in Rocky Mountain National Park in the Front Range of ...
Title, date and keywords based on information provided by the photographer. The towering Front Range is the first mountain range encountered by white settlers years ago, and travelers today, moving west along t... More
Hoover Dam, Static Towers & Lines, U.S. Highway 93, Boulder City, Clar...
Significance: It was constructed as an integral part of the control and protection system for the Hoover Dam switchyard complex, to protect the switchyards and transformer circuits from lightning strikes. Surv... More
Hoover Dam, Static Towers & Lines, U.S. Highway 93, Boulder City, Clar...
Significance: It was constructed as an integral part of the control and protection system for the Hoover Dam switchyard complex, to protect the switchyards and transformer circuits from lightning strikes. Surv... More
Lakeshore Road, Boulder Basin, Boulder City, Clark County, NV
Significance: Lakeshore Road and associated road features have been determined locally significant under National Register Criteria A and C. Construction of the road opened Lake Mead NRA, an early and major so... More
Lakeshore Road, Boulder Basin, Boulder City, Clark County, NV
Significance: Lakeshore Road and associated road features have been determined locally significant under National Register Criteria A and C. Construction of the road opened Lake Mead NRA, an early and major so... More
Lakeshore Road, Boulder Basin, Boulder City, Clark County, NV
Significance: Lakeshore Road and associated road features have been determined locally significant under National Register Criteria A and C. Construction of the road opened Lake Mead NRA, an early and major so... More
Pine Hills Station, Barracks, West Side of Boulder Creek Road at Engin...
Significance: The Pine Hills Barracks was one of the earliest guard stations constructed by the Civilian Conservation Corps (CCC) as part of the Depression Era economic revitalization plan by United States Gove... More
Pine Hills Station, Barracks, West Side of Boulder Creek Road at Engin...
Significance: The Pine Hills Barracks was one of the earliest guard stations constructed by the Civilian Conservation Corps (CCC) as part of the Depression Era economic revitalization plan by United States Gove... More
Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark C...
Significance: It is a National Historic Landmark, an American Civil Engineering Landmark, and the focus of an historic district listed on the National Register of Historic Places. The dam was constructed betwee... More
Hoover Dam, Explosives Magazines, About 75 feet west of Lower Portal T...
Significance: These two explosive magazines were constructed for storage of dynamite used in the early phases of construction of Hoover Dam, possibly as early as 1931 for blasting the route of the Lower Portal ... More
Hoover Dam, Explosives Magazines, About 75 feet west of Lower Portal T...
Significance: These two explosive magazines were constructed for storage of dynamite used in the early phases of construction of Hoover Dam, possibly as early as 1931 for blasting the route of the Lower Portal ... More
Hoover Dam, Arizona-Nevada Switchyard, U.S. Highway 93, Boulder City, ...
Significance: It is one of six switchyards built between 1935 and 1952 to provide terminals for major transmission lines carrying electricity to markets in California, Nevada, and Arizona. All of these faciliti... More
Hoover Dam, Arizona-Nevada Switchyard, U.S. Highway 93, Boulder City, ...
Significance: It is one of six switchyards built between 1935 and 1952 to provide terminals for major transmission lines carrying electricity to markets in California, Nevada, and Arizona. All of these faciliti... More
Boulder Fortress Pueblito, Crow Canyon, Dulce, Rio Arriba County, NM
Public domain photograph - New Mexico, United States, free to use, no copyright restrictions image - Picryl description
Hoover Dam, Los Angeles Relay Control Building, U.S. Highway 93, Bould...
Significance: It was a critical element of the Hoover Dam electrical generation and transmission system. Although it was associated by name with the Los Angeles Bureau of Power and Light 387.5/275 switchyard, t... More
Howard Ditch, East Boulder Community Park, Boulder, Boulder County, CO
Picryl description: Public domain image of field, irrigation, agriculture, water, free to use, no copyright restrictions.
Hoover Dam, Southern California Edison 138-KV Switchyard, U.S. Highway...
Significance: It was the second of six major Federal switchyards built at Hoover Dam. The switchyard was built to replace the Southern Sierras Power Company substation that had provided electricity for construc... More
Boulder Farm, Dunbarton Road, Hopkinton, Merrimack County, NH
Survey number: HABS NH-42 Building/structure dates: 1816 Initial Construction
Boulder Farm, Dunbarton Road, Hopkinton, Merrimack County, NH
Survey number: HABS NH-42 Building/structure dates: 1816 Initial Construction
Hoover Dam, Cable Hoist House, U.S. Highway 93, Boulder City, Clark Co...
Significance: It provided access to control cable tunnels from the power plant to the switchyard relay house, and a transformer in the lower level of the hoist house provided operating electricity to the switch... More
Hoover Dam, Los Angeles Bureau of Power & Light Lines 1-3, U.S. Highwa...
Significance: The transmission lines included pioneering technology in high-voltage transmission. The lines were crucial elements of the Hoover Dam electrical complex, particularly in the role played by Hoover ... More
Hoover Dam, Los Angeles Bureau of Power & Light Lines 1-3, U.S. Highwa...
Significance: The transmission lines included pioneering technology in high-voltage transmission. The lines were crucial elements of the Hoover Dam electrical complex, particularly in the role played by Hoover ... More
Hoover Dam, Metropolitan Water District Switchyard, U.S. Highway 93, B...
Significance: It was the second-largest Federal switchyard at Hoover Dam, the switchyard provided needed power for expansion of irrigation and municipal water supplies in California during and after WWII, but i... More
Hotel Kaaterskill from Boulder Rock, Catskill Mountains, N.Y.
Public domain photograph of a mountain pass, mountains, nature, mountain range, view, landscape, rocks, free to use, no copyright restrictions - Picryl description
Grand Canyon National Park Roads, Boulder Street Headwall No. 1, North...
Significance: This headwall is representative of rustic style road structures constructed by the Civilian Conservation Corps and other depression-era public works agencies within the western national parks duri... More
Hoover Dam, Southern California Edison 230-KV Switchyard, U.S. Highway...
Significance: It was an integral element of the Hoover Dam electrical generation and transmission system. This switchyard provided much-needed electricity during WWII to power Douglas, Vultee, and Northrup airc... More
Hoover Dam, Los Angeles Switch Yard, U.S. Highway 93, Boulder City, Cl...
Significance: It was the first and largest of the six major Federal switchyards at Hoover Dam. When the first stage of the switchyard began operations in 1936, it provided electricity at the highest voltages ev... More
Bluebird Dam, Rock Cabin, On Ouzel Creek 7 miles west of Allenspark, A...
Survey number: HAER CO-33-A Public domain photograph - historical image of Colorado, United States, free to use, no copyright restrictions image - Picryl description
![[Fall in North Boulder Canon] - stereoscopic view, public domain photorpaph](https://cache.getarchive.net/Prod/thumb/cdn18/L3Bob3RvLzIwMTkvMTAvMTMvZmFsbC1pbi1ub3J0aC1ib3VsZGVyLWNhbm9uLWRiYjAwZS0xMDI0LmpwZw%3D%3D/40/22/webp "[Fall in North Boulder Canon] - stereoscopic view, public domain photorpaph")
[Fall in North Boulder Canon] - stereoscopic view, public domain photo...
Part of series: Beauties of the Rocky Mountains. The albumen silver print is a photographic printing process that was widely used in the 19th century. It involves coating paper support with a mixture of egg w... More
![Mr. H.E. Eder and family at Bowlder [i.e. Boulder] Rock](https://cache.getarchive.net/Prod/thumb/cdn4/L3Bob3RvLzE5MDAvMDEvMDEvbXItaGUtZWRlci1hbmQtZmFtaWx5LWF0LWJvd2xkZXItaWUtYm91bGRlci1yb2NrLTEwMjQuanBn/40/31/webp "Mr. H.E. Eder and family at Bowlder [i.e. Boulder] Rock")
Mr. H.E. Eder and family at Bowlder [i.e. Boulder] Rock
Public domain photograph - Portrait, United States, free to use, no copyright restrictions image - Picryl description
Boulder, Colo. Disaster of Aug. 10, 1907
Train excursion stopping to allow passengers to view the ruins of fire which started in freight depot sheds. Stereo copyrighted by Ed Tangen. No. 250. No copyright renewal. cf. America's Yesterdays, p. 85. This... More
Ivy Baldwin breaking the record for tight-rope walking-rope 580 feet h...
No. 2964. Public domain photograph of stereoscopic card, free to use, no copyright restrictions image - Picryl description
Aerial view of Hoover Dam, near Boulder City, Nevada
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Title, date, and keywords provided by the photographer.... More
Aerial view of Hoover Dam, near Boulder City, Nevada
Picryl description: Public domain image of a power dam, cascade, free to use, no copyright restrictions.
Lake Mead National Recreation Area, Boulder City, Nevada
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Title, date, and keywords provided by the photographer.... More
Aerial view of Hoover Dam near Boulder City, Nevada
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Title, date, and keywords provided by the photographer.... More
Above Hoover Dam near Boulder City, Nevada
Digital image produced by Carol M. Highsmith to represent her original film transparency; some details may differ between the film and the digital images. Hoover Dam, once known as Boulder Dam, is a concrete ar... More
Continental Divide sign high in Rocky Mountain National Park in the Fr...
Title, date and keywords based on information provided by the photographer. The towering Front Range is the first mountain range encountered by white settlers years ago, and travelers today, moving west along t... More
High-country views in Rocky Mountain National Park in the Front Range ...
Title, date and keywords based on information provided by the photographer. The towering Front Range is the first mountain range encountered by white settlers years ago, and travelers today, moving west along t... More
Lakeshore Road, Boulder Basin, Boulder City, Clark County, NV
Significance: Lakeshore Road and associated road features have been determined locally significant under National Register Criteria A and C. Construction of the road opened Lake Mead NRA, an early and major so... More
Lakeshore Road, Boulder Basin, Boulder City, Clark County, NV
Significance: Lakeshore Road and associated road features have been determined locally significant under National Register Criteria A and C. Construction of the road opened Lake Mead NRA, an early and major so... More
Hoover Dam, Lower Portal Access Road, U.S. Highway 93, Boulder City, C...
Significance: It was an important feature in the construction of Hoover Dam. The road provided access to the bottom of Black Canyon at a point about one mile downstream from the dam construction site. Here a co... More
Hoover Dam, Lower Portal Access Road, U.S. Highway 93, Boulder City, C...
Significance: It was an important feature in the construction of Hoover Dam. The road provided access to the bottom of Black Canyon at a point about one mile downstream from the dam construction site. Here a co... More
New Fork River Bridge, County Road 136, Boulder, Sublette County, WY
Significance: The New Fork River Bridge is the only two span Kingpost Timber truss in the State. It is the most sophisticated of the few timber trusses still functional on the County Road System. As the best ... More
Resist nuclear madness! - A black and white photo of a group of people...
Public domain photograph - historical image of Colorado, United States, free to use, no copyright restrictions image - Picryl description
Pine Hills Station, Barracks, West Side of Boulder Creek Road at Engin...
Significance: The Pine Hills Barracks was one of the earliest guard stations constructed by the Civilian Conservation Corps (CCC) as part of the Depression Era economic revitalization plan by United States Gove... More
Pine Hills Station, Barracks, West Side of Boulder Creek Road at Engin...
Significance: The Pine Hills Barracks was one of the earliest guard stations constructed by the Civilian Conservation Corps (CCC) as part of the Depression Era economic revitalization plan by United States Gove... More
Bluebird Dam, On Ouzel Creek 7 miles west of Allenspark, Allenspark, B...
Significance: Completed ca. 1923, it is locally significant to Boulder County as an intact example of an early 20th century, and relatively uncommon, arch concrete dam. The dam documents an important engineerin... More
Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark C...
Significance: It is a National Historic Landmark, an American Civil Engineering Landmark, and the focus of an historic district listed on the National Register of Historic Places. The dam was constructed betwee... More
Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark C...
Significance: It is a National Historic Landmark, an American Civil Engineering Landmark, and the focus of an historic district listed on the National Register of Historic Places. The dam was constructed betwee... More
Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark C...
Significance: It is a National Historic Landmark, an American Civil Engineering Landmark, and the focus of an historic district listed on the National Register of Historic Places. The dam was constructed betwee... More
Hoover Dam, Arizona-Nevada Switchyard, U.S. Highway 93, Boulder City, ...
Significance: It is one of six switchyards built between 1935 and 1952 to provide terminals for major transmission lines carrying electricity to markets in California, Nevada, and Arizona. All of these faciliti... More
Hoover Dam, Arizona-Nevada Switchyard, U.S. Highway 93, Boulder City, ...
Significance: It is one of six switchyards built between 1935 and 1952 to provide terminals for major transmission lines carrying electricity to markets in California, Nevada, and Arizona. All of these faciliti... More
Hoover Dam, Los Angeles Relay Control Building, U.S. Highway 93, Bould...
Significance: It was a critical element of the Hoover Dam electrical generation and transmission system. Although it was associated by name with the Los Angeles Bureau of Power and Light 387.5/275 switchyard, t... More
Bureau of Mines Boulder City Experimental Station, Ore Dressing Pilot ...
Significance: Building 600, as part of the Date Street Complex, was a component of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Bould... More
Hoover Dam, U.S. Highway 93 Nevada Segment, U.S. Highway 93, Boulder C...
Significance: This segment of U.S. Highway 93 was constructed by Six Companies, Inc., as a finishing element to Hoover Dam. The segment includes stone parapet walls built in 1932 that display extruded-mortar st... More
Hoover Dam, Southern California Edison 138-KV Switchyard, U.S. Highway...
Significance: It was the second of six major Federal switchyards built at Hoover Dam. The switchyard was built to replace the Southern Sierras Power Company substation that had provided electricity for construc... More
Boulder Farm, Dunbarton Road, Hopkinton, Merrimack County, NH
Survey number: HABS NH-42 Building/structure dates: 1816 Initial Construction
Hoover Dam, Nevada State Switchyard, U.S. Highway 93, Boulder City, Cl...
Significance: It was the smallest of the six major Federal switchyards at Hoover Dam. This switchyard was constructed to be the principal point at which Nevada's allocation of power from Hoover Dam could be del... More
Hoover Dam, Nevada State Switchyard, U.S. Highway 93, Boulder City, Cl...
Significance: It was the smallest of the six major Federal switchyards at Hoover Dam. This switchyard was constructed to be the principal point at which Nevada's allocation of power from Hoover Dam could be del... More
Hoover Dam, Nevada State Switchyard, U.S. Highway 93, Boulder City, Cl...
Significance: It was the smallest of the six major Federal switchyards at Hoover Dam. This switchyard was constructed to be the principal point at which Nevada's allocation of power from Hoover Dam could be del... More
Hoover Dam, Los Angeles Bureau of Power & Light Lines 1-3, U.S. Highwa...
Significance: The transmission lines included pioneering technology in high-voltage transmission. The lines were crucial elements of the Hoover Dam electrical complex, particularly in the role played by Hoover ... More
Hoover Dam, Los Angeles Bureau of Power & Light Lines 1-3, U.S. Highwa...
Significance: The transmission lines included pioneering technology in high-voltage transmission. The lines were crucial elements of the Hoover Dam electrical complex, particularly in the role played by Hoover ... More
Hoover Dam, Metropolitan Water District Switchyard, U.S. Highway 93, B...
Significance: It was the second-largest Federal switchyard at Hoover Dam, the switchyard provided needed power for expansion of irrigation and municipal water supplies in California during and after WWII, but i... More
Bureau of Mines Boulder City Experimental Station, Electrolytic Mangan...
Significance: Building 500, as part of the Date Street Complex, was a component of the Bureau of Mines Electrometallurgical Research Facility located in Boulder City. As such, it is within the designated Bould... More
Boulder Bridge, Spanning Rock Creek at Beach Drive, South of Joyce Roa...
Significance: Boulder Bridge is one of the earliest extant bridges in Rock Creek Park. Constructed in 1902, the bridge exemplifies the idea of rustic architecture in the early twentieth century National Parks.... More
Hotel Kaaterskill from Boulder Rock, Catskill Mountains, N.Y.
Public domain photograph - panorama, United States, free to use, no copyright restrictions image - Picryl description
Hoover Dam, U.S. Highway 93 Arizona Segment, U.S. Highway 93, Boulder ...
Picryl description: Public domain image of a mine, mining, free to use, no copyright restrictions.
Grand Canyon National Park Roads, Boulder Street Headwall No. 1, North...
Significance: This headwall is representative of rustic style road structures constructed by the Civilian Conservation Corps and other depression-era public works agencies within the western national parks duri... More
Hoover Dam, Southern California Edison 230-KV Switchyard, U.S. Highway...
Significance: It was an integral element of the Hoover Dam electrical generation and transmission system. This switchyard provided much-needed electricity during WWII to power Douglas, Vultee, and Northrup airc... More
Hoover Dam, Southern California Edison 230-KV Switchyard, U.S. Highway...
Significance: It was an integral element of the Hoover Dam electrical generation and transmission system. This switchyard provided much-needed electricity during WWII to power Douglas, Vultee, and Northrup airc... More
![[North Boulder Falls, Rocky Mountains] - stereocsopic card](https://cache.getarchive.net/Prod/thumb/cdn4/L3Bob3RvLzIwMTkvMDkvMjYvbm9ydGgtYm91bGRlci1mYWxscy1yb2NreS1tb3VudGFpbnMtZWE1M2RjLTEwMjQuanBn/40/22/webp "[North Boulder Falls, Rocky Mountains] - stereocsopic card")
[North Boulder Falls, Rocky Mountains] - stereocsopic card
Part of series: Beauties of the Rocky Mountains. The albumen silver print is a photographic printing process that was widely used in the 19th century. It involves coating paper support with a mixture of egg w... More
Hoover Dam, Metropolitan Water District Line 1, U.S. Highway 93, Bould...
Significance: The transmission line was a critical element of the Hoover Dam electrical generation and transmission system. The line provided Hoover Dam power for development of irrigation and municipal water d... More