After about a year of intending to, I finally got to Mare Island---what a treasure! If anyone is in the San Fransico area and looking for something different, this one by three mile long island should be worth the effort. While much has been torn down thanks to our congressional representatives, and the nature of the place is changing---a housing project is being built and much of the industrial area taken over by companies not too keen on trespassers---a lot remains of the old brick and stone warehouses and magazines, officers quarters, fall out shelters, and other buildings and structures including drydock #1---the first granite drydock on the west coast, and St. Peter's Chapel, the oldest Navy Chapel standing with the largest collection of Tiffany designed windows in one west of the Rockys. There is the cool industrial waterfront plus a couple of thousand acres of marshland bird habitat. "Sidewheelers to Nuclear Power: A Pictorial Essay Covering 123 Years At The Mare Island Naval Shipyard" Written by Lemmon and Michaels and published by Leeward is a must read to get background information and the historical perspective. The two hour guided tour offered by the Mare Island Historical Foundation((call 24hrs ahead since they are by arrangement only) will get you past the security guards and offer a chance to scope out the terrain and situation. Many places like the old cemetary and St. Peters are under lock and key to discourage vandalism. These tours are only two hours long, so I'd recommend contacting the historical foundation afterward to arrainge for a private guide for a certain number of hours and returning to the island to shoot then. There are other locations on the island that you can access on your own, and your guide can offer suggestions on how and when to get past the security guards. Cheers!