Researchers made a surprising find when diving in the waters off Hawaii: a large US naval tanker that had been sitting unseen in 80 feet of water for nearly 60 years.

"I turn around, and this giant, looming structure, so eerie," Melissa Price, a maritime archaeologist, told Hawaii News Now.

Price was one of three divers to discover the Mission San Miguel on Aug. 3 off the coast of Hawaii. During 1957 trip from Seattle to Guam, it hit a reef in the area and sank.

The crew was able to escape, but the ship went down.

"I had to stare at it for a little bit, then I started freaking out under water, screaming and motioning," said Rebecca Weible, a UH Manoa Marine Biology student who was diving with Price.

As a U.S. naval tanker in World War II and the Korean War, Mission San Miguel transported fuel for military machines. It received several commendations for its service.

"This is a ship that wasn't a glamorous part of World War II history, but was an important part," said Kelly Keogh, Maritime Heritage Coordinator for the Papahanaumokuakea Marine National Monument.

The Mission San Miguel is now in the protected waters of the Papahanaumokuakea monument. It will be mapped and studied on the ocean's floor.

"It's really very, very exciting discovery for the monument," Jason Raupp, who led the dive team that discovered the vessel.