is the main west-to-east interstate highway in the county, and serves as the unofficial dividing line between northern and southern Baker County. It enters the county from Osceola National Forest and contains five interchanges within the county; the first being US 90 in Olustee (Exits 324), followed by Baker CR 229 south of Sanderson and Baker CR 125 south of Glen St Mary. The last two interchanges are in Macclenny; SR 121 (Exit 335), and SR 228 (Exit 336). Beyond this point I-10 runs through Nassau and Duval Counties into Downtown Jacksonville. was the primary west-to-east route through Baker County until it was succeeded by Interstate 10. runs west to east through the northwest portion of the county, beginning at the northeast corner of Columbia County, then passing through John M. Bethea State Forest and becoming Georgia State Route 94 after crossing the bridge over the Saint Mary's River. is a south to north road that runs southwest to northeast from Raiford in Union County to just before the interchange with Interstate 10, and then straight south to north through downtown Macclenny and later towards rural Baker County, until it crosses a series of bridges over the Saint Mary's River where it takes a long journey through Georgia and South Carolina as a tri-state de facto auxiliary route from U.S. Route 21 in Rock Hill, South Carolina. is a short northwest-to-southeast state highway in Macclenny that has two county extensions. The first is a south-to-north extension beginning at US 90 leading to SR 121 north of the town limits. The second is a bi-county extension running southeast of Interstate 10 to US 301 in Duval County near the resumption of a state road which passes through Westside Jacksonville, Downtown Jacksonville and all the way to the Hogan section of Southside Jacksonville.
is the main west-to-east interstate highway in the county, and serves as the unofficial dividing line between northern and southern Baker County. It enters the county from Osceola National Forest and contains five interchanges within the county; the first being US 90 in Olustee (Exits 324) followed by Baker CR 229 south of Sanderson and Baker CR 125 south of Glen St Mary. The last two interchanges are in Macclenny; SR 121 (Exit 335) and SR 228 (Exit 336). Beyond this point I-10 runs through Nassau and Duval Counties into Downtown Jacksonville. was the primary west-to-east route through Baker County until it was succeeded by Interstate 10. runs west to east through the northwest portion of the county, beginning at the northeast corner of Columbia County, then passing through John M. Bethea State Forest and becoming Georgia State Route 94 after crossing the bridge over the Saint Mary's River. is a south to north road that runs southwest to northeast from Raiford in Union County to just before the interchange with Interstate 10, and then straight south to north through downtown Macclenny and later towards rural Baker County, until it crosses a series of bridges over the Saint Mary's River where it takes a long journey through Georgia and South Carolina as a tri-state de facto auxiliary route from U.S. Route 21 in Rock Hill, South Carolina. is a short northwest-to-southeast state highway in Macclenny that has two county extensions. The first is a south-to-north extension beginning at US 90 leading to SR 121 north of the town limits The second is a bi-county extension running southeast of Interstate 10 to US 301 in Duval County near the resumption of a state road which passes through Westside Jacksonville, Downtown Jacksonville and all the way to the Hogan section of Southside Jacksonville.