PEARL HARBOR, Hawaii -- A team of maritime archaeologists just returned on Thursday from the Northwest Hawaiian Islands, where they discovered two shipwrecks of whaling ships that have been lost since the 1830s.

A National Oceanic and Atmospheric Administration research ship docked at Pearl Harbor on Thursday after a monthlong expedition to find and document shipwrecks in the Northwest Hawaiian Islands.

The scientists were thrilled because they found two previously undiscovered shipwrecks.

They searched by towing divers on sleds behind a moving boat. The divers scanned the ocean floor for signs of the long-lost ships.

"When we finally come across the ballast pieces or the anchors, or even the cannons that were aboard some of these early ships, we start whooping it up under water, grab tape, measure, getting the rest of the team really a wonderful moment," NOAA archaeologist Hans Van Tilburg said.

The wreckage has been lying on the ocean floor for the better part of two centuries. The reefs and atolls claimed many ships back in the early 1800s.

"This area wasn't mapped very well back in the day. Early explorers didn't have it down to pat. So, unfortunately, they came to grief on the reef," NOAA archaeologist Tane Casserley said.

Most of the sailors survived and made it to nearby atolls and islands where they survived for months, building boats out of the wreckage to escape.

"Diving on the wreck up there is spectacular. You have natural beauty of marine life and coral; you have intact pristine wrecks, where the wood is gone, but still got the giant structure there, the anchors, tripods and things. It's spectacular. You don't see this anywhere else in the world," Casserley said.

The discovery is a look through a window into the 19th-century heritage of whaling in the beautiful and remote region.