A stately maroon-and-white bridge stands alone in the forest, a sentinel guarding the worn dirt road. Birds chirp softly from the surrounding fall foliage, seemingly hesitant to disturb the peace. Though covered bridges were once just a part of a journey—a pass-through to another place—today, they mark my destination. Marshall Bridge, built in 1917, is one of 31 historic covered bridges (the oldest date to 1856) in Parke County, Indiana. They're scattered around this western chunk of the state like treasure waiting to be found. Out here, it's easy to think of the bridges as portals back in time. I can imagine the clop-clop of horses' hooves on the wooden slats echoing through the trees, punctuating the birdsong. Though I've driven only a few miles, this feels a world away from the bustling scene I've just left—The Parke County Covered Bridge Festival. Held over 10 days each October, the event started in 1957 as a way to both highlight the bridges and unite the county's communities in a tourism effort. Today, it's Indiana's largest festival.