Songo Lock is the last surviving lock of the Cumberland and Oxford Canal, a 19th-century canal in southern Maine, United States. The lock is located on the Songo River, just above its confluence with the Crooked River at the northern end of Sebago Lake State Park in the town of Naples. The lock, built in 1830, is now used primarily during the summer months by pleasure craft. It was listed on the National Register of Historic Places in 1970.