On this day in 1851, the contract to construct the Port Isabel lighthouse was let by the United States government.
The brick lighthouse stands near State Highway 100 in southeastern Cameron County. It is fifty-seven feet high, and projects eighty-two feet above sea level. The original light was visible for fifteen miles. The tower has been used mainly for observation, first during the Cortina War, then during the Civil War and both world wars. It received a state historic marker in 1936. In the 1990s the tower with its mercury-vapor light was still marked on sea charts as an aid to navigation. The site is owned by the Texas Parks and Wildlife Department, but daily operations were transferred to the city of Port Isabel following the construction of a new visitor's center in 1996. Large-scale restoration efforts were completed in 2000.