The Franklin County, New York, Highway Department maintains of roads as county routes. All county routes in Franklin County are signed with a yellow and blue pentagon. Formerly, the county used a green square marker that was unique to the county. There is no apparent pattern to how routes are assigned; however, no active county route has the same number as any of the county's U.S. Highways or New York state touring routes, with the exception of County Route 3 (CR 3). The section of New York State Route 374 (NY 374) that lies north of U.S. Route 11 (US 11) is owned and maintained by Franklin County and is thus co-signed as a state touring route and as a Franklin County route. The longest route in the county is CR 26, which was once NY 99.