The History of Cayuga Lake
Carved by glaciers, Cayuga Lake is the longest and second deepest of the Finger Lakes, at 38.2 miles long and 435 feet deep at its deepest point. It reaches 53 feet below sea level, and along with Seneca Lake, it is among the deepest lakes in North America.

Steamboats on the Southern end of Cayuga Lake, Walton

Over 350 million years ago, during the Devonian period, the whole Finger Lakes area was under a shallow saltwater sea. Over time, sediments from mountains to the east filled in the sea, eventually forming the typical shale, siltstone and sandstone rock found in this area. The skeletal remains of sea creatures formed layers of limestone, and deposits from the seawater created the thick salt layers now mined from below the lake. Cayuga Lake as we know it was formed during the next recorded chapter of local geological history -- the Ice Age. Prior to the start of Ice Age two million years ago, what is now Cayuga Lake was a valley with a north flowing river running through it. A series of ice sheets flowing southward from Hudson Bay, and then receding, carved out the Finger Lakes. These glaciers were often on the magnificent scale of over a mile high.