Mare Island Naval Shipyard, Shell House No. 1, Railroad Avenue, west side near Maseda Road, Vallejo, Solano County, CA

Significance: Building A3 is a contributing element of the Mare Island Historic District. Building A3 is important as the best example of the various brick magazines that were built in the Ammunition Depot Area during the 1850s and 1860s. While arguably less interesting architecturally than Building A1, the sandstone magazine, the brick magazines are nonetheless key aspects of the historic scene in this pat of the island. Only a few years younger than Building A1, Building A3 is one of the oldest military buildings anywhere in California.
Survey number: HABS CA-1543-CN
National Register of Historic Places NRIS Number: 75002103