State Route 300, also called the Georgia-Florida Parkway, is a 116 miles (187 km) long route that runs from Florida State Road 57 at the Florida-Georgia state line south of Thomasville in Thomas County, north to I-75 in Cordele in Crisp County.

From south to north, SR 300 goes through Thomasville, Meigs, Pelham, Camilla, Baconton, Albany, Oakfield, Warwick, and Cordele.

State Road 300 is concurrent with US 19/State Route 3 from the southern terminus, north to Albany. South of the state line, US 19 eventually intersects I-10 and continues south to St. Petersburg, Florida.

In Florida, US 19 becomes the Florida-Georgia Parkway.

Much of SR 300 follows the route of cancelled Interstate 175, which would have connected the city of Albany to the Interstate system via I-75. The portion of SR 300 that parallels the now-defunct I-175 between Cordele and Albany was formerly known as SR 257, and the portion of SR 300 from Albany to the Florida State Line was SR 333.

The original SR 300 was a route between Monticello and US 129/US 441/SR 24 near Rock Eagle 4-H Center.

With the forthcoming completion of four-laning of US 19, activities are underway to redefine the Georgia-Florida Parkway to be coincident with the Magnolia Highway, which is US 19 between St. Petersburg and Atlanta.