"There is no doubting that the Great Wall of China is, er, is one of the greatest historical artifacts in the world. And to be able to see and experience a part of it in a way that, uh, very few other people get to do, with all the added romance of being underwater, I, I think that's a very special experience and it's a way to get in touch with history and a way that few people get the opportunity to do."
Built to ward off invaders, the Great Wall of China was constructed in sections over several centuries. Construction began in the 3rd century BC. Sections were then built and rebuilt through the 16th century A.D.
In the early 1980s, the Chinese government flooded the northern coastal area of Tianjin crossed by the Great Wall to resolve water shortages. It's reported that most of the submerged section of the Great Wall now lies at a maximum depth of 65 feet.