U.S. Highway 23
Maintained by FDOT
North end:	US 1 / US 23 / US 301 / SR 4 at Georgia State line
Major junctions:	I-295 near Jacksonville US 1 in Jacksonville I-95 in Jacksonville
South end:	US 1 / US 17 / SR 115 in Jacksonville
Counties:	Nassau, Duval
Florida State and County Roads < SR 23 SR 24 > United States Numbered Highways List – Bannered – Divided – Replaced

U.S. Highway 23 (US 23) is a United States Numbered Highway that runs from Jacksonville, Florida to Mackinaw City, Michigan. In the US state of Florida, US 23 is concurrent with U.S. Route 1 south of Alma, Georgia, except in downtown Downtown Jacksonville. US 23 is also concurrent with U.S. Route 301 between Homeland, Georgia and Callahan.

US 23 signed along the following unsigned state roads:

• SR 139 from downtown Jacksonville to the Martin Luther King Jr. Parkway in Jacksonville
• SR 15 from the Martin Luther King Jr. Parkway in Jacksonville to Georgia.

A US 23 shield used in Florida prior to 1993

U.S. Route 23
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