Opened in 1905, the cut across the peninsula that is now Miami Beach was authorized by the U.S. government (hence the name), in order to provide a direct route from the Atlantic Ocean on the east to the seaport on Biscayne Bay to the west, without having to detour southward. The cut across the mangroves and beach at the southern end of the peninsula created Fisher Island, which except for the extreme northeast corner, is part of unincorporated Miami-Dade County, Florida. The now-famous South Beach is to the north of the cut.