An urban explorer’s paradise, the San Francisco Naval Shipyard was a United States Navy shipyard located on nearly 700 acres of waterfront at Hunter’s Point in the southeast corner of the city.

It’s difficult to find agreeing dates for when the base was officially closed but it’s obvious nothing has really gone on there for quite some time. It seems the main impediment to rehabilitation for Hunter’s Point is the prohibitively high cost of cleaning up all the toxic substances dumped there over the decades. It was the military’s chosen site for the Naval Radiological Defense Laboratory and, according to hundreds of menacing yellow placards posted throughout the property, radioactive contamination is cause for concern.

Not only are there a lot of pollutants dumped into the water over more than a century of use as a major shipyard to worry about, but the site also served as the launch point for key components used in the construction of the first atomic bomb. The components were loaded onto the U.S.S. Indianapolis in 1945 at Hunter’s Point for transfer.

Originally, Hunter’s Point was a commercial shipyard dating back to 1870. The original docks, built on solid rock, were thought to be the largest in the world at the time. At more than 1,000 feet in length, they could host some of the largest warships and passenger steamers in the world. Between World War I and World War II, the site was contracted from private owners for the Navy because the sixty-five-foot depth right off the coast was greater than anything else available in the area.