SULLIVANS ISLAND, S.C. — The last major lighthouse built in the United States is showing its age at 50, but the National Park Service is reviewing a management plan to maintain the beacon that still shines 27 miles out into the Atlantic Ocean on clear nights.

The black and white Charleston Light rising 140 feet above this affluent beach community on the northeast side of Charleston Harbor was commissioned in 1962.

It's unique among the hundreds of lighthouses in the nation in that its tower is triangular, the better to withstand hurricane winds that periodically pound the coast. And instead of walking up the tower on a spiral staircase, the lantern room can be reached by elevator.

Designed by Jack Graham, who studied under noted American architect Louis Kahn at the University of Pennsylvania, the light was the second-brightest in the Western Hemisphere when it was commissioned with 26 million candlepower. That proved much too bright for the locals, and the Coast Guard reduced the light to 1.5 million candlepower.

Also, island residents didn't care for the lighthouse's original red-orange color — like that on Coast Guard helicopters. So the tower was painted black and white.

Charleston Light, known locally as the Sullivans Island lighthouse, replaced what is now the Morris Island lighthouse.

People are always attracted to lighthouses, said Rick Dorrance, the chief of resource management at the Fort Sumter National Monument.

There are about 600 lighthouses in the nation, according to the Wisconsin-based United States Lighthouse Society.

The Fort Sumter National Monument includes the fort in the harbor where the Civil War began, the Charles Pinckney Historic Site in nearby Mount Pleasant, as well as Fort Moultrie and the U.S. Coast Guard Historic District on Sullivans Island.

The Park Service acquired the lighthouse and adjoining Coast Guard buildings in 2008 under the National Historic Lighthouse Preservation Act, Dorrance said. The Coast Guard put the lighthouse on its surplus property list with lighthouses becoming obsolete in an era of global-positioning-system navigation.

Under the act, anyone who acquires a lighthouse must maintain the structure and provide public access. In this case, the Coast Guard keeps Charleston Light shining, and it is still an aid to navigation. The National Park Service maintains the light tower and associated buildings.

The Park Service provides public access four times a year to the property, with the next time this Tuesday on National Lighthouse Day.

There has been no access to the inside of the lighthouse in recent months. Lead paint is flaking off the side and gets into the air when people walk on it, Dorrance said. Coast Guard personnel have to wear protective suits when they service the light.

The Park Service recently received public comment on a draft management plan for the next five to 10 years. One of the alternatives in the plan would be to paint and provide public access to the lantern room and perhaps the catwalk around it at the top.