Peaks Island in Casco Bay is a destination for tourists and Maine residents alike, but did you know that there's an abandoned fort on the island that you can explore but you better bring a flashlight.

Battery Steele was built in 1942 during World War II to defend Portland Harbor with two 16" guns that could shoot a 2240 pound shell up to 30 miles. According to the Peaks Island Land Preserve website, it was one of the largest batteries ever built in the United States.

Today, the guns are gone, but many of the structures still remain, overgrown and covered in graffiti. It could easily be used in a scene of some post-apocalyptic movie.

Battery Steele has been listed on the National Register of Historic Places since 2005 and so it's story can be told for generations to come. You're free to roam what remains of Battery Steele, but you'll want a flashlight since the battery is deep and dark in many places as you'll see in this video exploring Battery Steele from Atlas Obscura.