US 15 and US 29 run concurrently as a four-lane divided highway around the east side of Culpeper, where the highways cross over the Washington District rail line and meet US 522 and SR 3 (Germanna Highway) at a diamond interchange. US 15 and US 29 pass under the rail line and meet the northern end of US 15 Business and US 29 Business at a partial cloverleaf interchange. The highways parallel the Washington District through Brandy Station and by Culpeper Regional Airport to the town of Remington, where the road crosses the Rappahannock River into Fauquier County. US 15 and US 29 pass to the north of the town, which is directly served by US 15 Business and US 29 Business (James Madison Street). Immediately north of the northern junction with the business routes, US 15 and US 29 meet the southern end of SR 28 (Catlett Road), which follows the rail line toward Manassas.