Henry Flagler had a vision: link Key West to the mainland with a railroad. Many said it couldn't be done, but the vision was fulfilled in 1912 when a steam-powered locomotive chugged into Key West, the first train to use the Florida Overseas Railway. Now, a paved multi-use trail follows the old rail line, allowing users to intimately experience coastal hamlets and take in views of shimmering Gulf and ocean waters. It joins a long list of outstanding Florida walking, hiking and biking trails. John Pennekamp, the nation's first undersea park, can be found along the way. The 70-mile trail will eventually grow to 106.5 miles long, extending the entire length of the Keys. Although not yet contiguous, the current length is still worth the ride.