U.S. Route 117 Alternate (US 117 Alt) is a alternate route of US 117 running through the towns of Calypso, Mount Olive, and Brogden. The highway travels from US 117 in Calypso to US 117 north of Brogden. US 117 Alternate was established on November 28, 1988. US 117 Alternate was a renumbering of US 117 Business through Calypso and Mount Olive, and a partial renumbering of US 117 between Mount Olive and Brogden. The routing of US 117 Alternate consists of the former routing of US 117 prior to the completion of a bypass around Calypso, Mount Olive, and Brogden.
|formed=1960
|history=Signed as US 117A from 1951 to 1960