Official U.S. Coast Guard Photographs. America's oldest lighthouse, has pointed the way for mariners for 754 years. The 89-foot Boston tower with its winding staircase and two-million candlepower beacon contrasts vividly with Charleston Light Station, South Carolina. The modern 169-ft. Charleston Light is a three-side tower housing, 28-milion candlepower light. Coast Guardsman who serviced the light were relieved to see an elevator installed when it was built in 1962. No other U.S. lighthouse has this convenience, The Coast Guard has maintained all U.S. lighthouses since 1939 when the former Lighthouse Service was merged with the Coast Guard.