Mare Island was the first permanent US naval installation on the West coast, and Commodore David Farragut was its first commander, a bit of history of which I was unaware.
“For over a century, Mare Island was the Navy’s Mare Island Naval Shipyard. The growing size and number of the country’s naval fleet was making older facilities obsolete and led to increased building and refitting of shipyards nationally. In 1872 the US Public Works Department commenced construction of a 508-foot (155 m) drydock on the island, setting it on a foundation of cut granite blocks. The work was completed in 1891.”
That would be the drydock pictured above, I believe.
Mare Island was shut down in 1993 as part of the Base Realignment and Closure report, and the city of Vallejo has been working at converting and preserving the site ever since. Mare Island is a National Historic Landmark, a State Historical Landmark, and in 1999 the city of Vallejo added Mare Island to the National Register of Historic Districts.
Currently, the drydocks at Mare Island are being used by a private company to recycle ships from the mothball fleet in Suisun Bay.
Image credit: Jeremy Blakeslee