US 17 continues northwest as Warrenton Road, a four-lane divided highway that passes businesses and heads northeast of a park and ride lot. The road enters more rural areas and passes through Berea, Paynes Corner, Hartwood, and Storck on its way to the Fauquier County line at Deep Run. The U.S. Highway continues northwest as Marsh Road through Goldvein, Sumerduck, and Morrisville before crossing over Norfolk Southern Railway's Washington District and intersecting SR 28 (Catlett Road) in Bealeton. At Opal, US 17 joins US 15 and US 29 (James Madison Highway) to head north to Warrenton. At the three U.S. Highways' intersection with their respective business routes, the highway becomes a freeway. US 17, US 15, and US 29 have a diamond interchange with SR 643 (Meetze Road/Lee Street) before the combination partial cloverleaf and directional interchange where US 17 diverges from US 15 and US 29, which head toward Washington as Lee Highway, and all three highways meet the northern end of US 15 Business and US 29 Business (Lee Highway), which are used to reach the eastern end of US 211. US 17 briefly passes through the town limits of Warrenton while heading northwest to a partial interchange with the northern end of US 17 Business (James Madison Highway).