Exploring the Most Dangerous Abandoned Fort in Louisiana. This is one of Louisiana’s most dangerous abandoned locations, a crumbling brick fortress swallowed by the swamp and forgotten by time. Built in the early 1800s as part of America’s coastal defense system, this structure once stood strong against storms, invasions, and war — but nature always wins. After a massive fire destroyed the barracks in 1867, the fort was abandoned, left to rot as the bayou slowly reclaimed it. Today, it’s one of