I toured the USS Cobia, a World War II submarine that sank 13 ships and received 4 battle stars. Take a look inside.

• The USS Cobia submarine sank 13 ships and rescued seven downed American pilots during World War II.
• The US Navy submarine is open to the public for tours at the Wisconsin Maritime Museum in Manitowoc.
• Visitors can walk through its torpedo rooms, control room, and bunks that held its crew of 80 men.

The USS Cobia, a US Navy submarine exhibited at the Wisconsin Maritime Museum in Manitowoc, has been remarkably well-preserved and painstakingly restored to offer visitors an authentic look into its World War II combat service.

The USS Cobia sank 16,835 tons of shipping during the war, including a Japanese ship loaded with 28 tanks in a move credited with helping the US win the Battle of Iwo Jima in 1945. The submarine received four battle stars for its wartime service.

“She made six war patrols, sank 13 enemy ships, and rescued seven downed American pilots that were forced to ditch in the ocean,” Mark Becker, a US Navy submarine veteran and volunteer at the Wisconsin Maritime Museum, told Business Insider of the USS Cobia. “So she’s not only a life taker, she’s a life saver.”

Thanks to the efforts of the museum’s staff and volunteers, two of its engines still run, many of the switches and buttons still work, and its radar is one of the oldest operational radar systems in the US. It’s in such good condition that the Wisconsin Maritime Museum even allows guests to stay overnight on the USS Cobia in a “Sub Bnb” experience.

“Maintaining the vessel itself is a huge undertaking for a nonprofit like us,” museum director Kevin Cullen told BI, adding that it costs around $100,000 a year to keep the submarine in working order. “These vessels weren’t supposed to be here this long.”

I visited the museum in December to tour the USS Cobia. Take a look inside.