The Davis Island Lock and Dam Site on the Ohio River in Avalon, Pennsylvania, is the site of the former Davis Island lock that was completed in 1885.

The lock and dam existed from 1878 to 1922, designed by William Emery Merrill and the U.S. Army Corps of Engineers.

It officially opened on October 7, 1885, with a large dedication ceremony.

It was the first of 51 Chanoine type dams that were built by the Corps of Engineers between 1878 and 1929.

It was listed on the National Register of Historic Places on August 29, 1980 and designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1985.