Have you heard about this? Excavators at Ground Zero, the former World Trade Center site, have found the hull of an 18th century sailing ship! Turns out it apparently was filled with rocks and sunk to help fill in swampy areas. (In essence, "making" land to use and build on. Developers use fill dirt for the same purpose today.)
During the Gold Rush, many ships were abandoned in the San Francisco harbor after their crews deserted to head for the mining camps. These ships were often used as fill in the same way...and that's one reason why San Francisco has some very unstable areas when earthquakes come to call. Rotten wood and nails do not a sturdy foundation make.