Sabine Pass, the natural opening between Sabine Lake and the Gulf of Mexico, separates Jefferson County, Texas, and Calcasieu Parish, Louisiana, at the head of the Sabine-Neches Waterway. Sabine Pass was the site of the battle of Sabine Pass in 1863. Federal efforts to improve navigation across the bar that once blocked the entrance of deepwater vessels to the Sabine River began during the 1870s. In 1979 well over seventy-five million tons of cargo passed through the Sabine Pass jetties, which extended nearly three miles into the Gulf. The Sabine Pass lighthouse, built in 1856, is located in southwestern Cameron Parish, Louisiana, at the mouth of the Sabine River.