 SR 235 passes a recreation of George Washington's Gristmill, crosses Dogue Creek, and passes an entrance to Fort Belvoir.The state highway curves to the northeast and intersects Old Mill Road and Ferry Landing Road, both part of SR 623, an oblique intersection just west of Grist Mill Park.SR 235 continues east, curving toward the south and intersects another Old Mill Road and SR 623, now named Old Mount Vernon Road, before reaching the Mount Vernon plantation, a National Historic Landmark.