Maine lighthouses free to the public one day only this September

Twenty-five Maine lighthouses will be open and free to the public on Saturday, September 9, as part of the state’s ninth annual Open Lighthouse Day.

The event in the past has proven to be a tourism boon, drawing between 15,000 and 18,000 visitors annually, including from the Boston area. The Coast Guard, Maine’s tourism wing, and the American Lighthouse Foundation are sponsoring the visits.

Maine has more coastal lighthouses than anywhere else in the U.S., according to its Office of Tourism. The 25 that will be free to tour on September 25 represent nearly 40 percent of the 66 lighthouses still standing in the state. There were at least 70 about a century ago.

Visitors on Open Lighthouse Day may encounter fees for parking, but entry and tours of the lighthouses will be no charge.

Here’s a rundown of all 25.