Day trip to the keys to watch the sunset on the Seven Mile Bridge. There’s a Sunrise & Sunset every single day and they’re absolutely free. Sunset is still my favorite color and rainbow is second. We should take inspiration from the beauty in nature. The Seven Mile Bridge is a bridge in the Florida Keys, in Monroe County, Florida, United States. It connects Knight's Key (part of the city of Marathon, Florida) in the Middle Keys to Little Duck Key in the Lower Keys. Among the longest bridges in existence when it was built, it is part of the Overseas Highway in the Keys, which is part of the 2,369-mile U.S. Route 1.