The Falls of the Ohio is one of the largest naturally exposed Devonian Fossil Beds in the world. The “Falls” is in fact not one waterfall, but a series of rapids, which prior to construction of the various locks and dams, dropped 26 feet in about 3 miles, forming a series of rapids, waterfalls, and chutes. Now, the drop in elevation occurs entirely at the lock and dam structures. The normal upper and lower water levels are 37 feet apart; the normal upper pool elevation is 420 feet above mean sea level and the lower pool is 383 feet above mean sea level. The area has a rich cultural and natural history. The area was used as a crossing point for animals, and as a hunting area for Native Americans. More than 260 bird species have been sighted at the Falls, and a wide variety of other wildlife is present. In the river’s natural state, boats could traverse the falls during periods of high water only, so the area became a stopping point while goods were unloaded and portaged, thus creating the towns of Louisville, Clarksville and Jeffersonville. When there was enough water, boats could attempt to run one of three chutes, or passages through the Falls, but this required expertise and boats often wrecked during the attempt. In 1830, the 1.9 mile privately owned and operated Portland Canal with a 3 flight lock at the lower end was finished. By 1930, a new concrete and steel dam was built in conjunction with a hydroelectric plant project of the LG&E company. The dam was constructed in an “L” shape, extending from the Indiana shore and gave the Falls area its present look. See the webpage for McAlpine Locks and Dam for more history on the locks and dam.