US 340 enters Front Royal along four-lane Royal Avenue; the highway drops to two lanes at SR 55 (South Street), from which the state highway joins U.S. Highway. The two highways pass the Warren County Courthouse at the west end of the Front Royal Historic District. US 340 and SR 55 meet US 522 next to Rose Hill at Commercial Avenue, from which the other U.S. Highway joins the concurrency. The three highways follow four-lane Royal Avenue north to a right-angle curve where the three routes curve onto 14th Street and then turn north onto four-lane divided Shenandoah Street. US 340, US 522, and SR 55 cross Norfolk Southern's Hagerstown District rail line and the South Fork Shenandoah River into the Riverton area of Front Royal, where SR 55 splits to the west onto Strasburg Road. The two U.S. Highways then cross the North Fork Shenandoah River and Norfolk Southern Railway's B-Line just west of the confluence of the two Shenandoah River forks. US 340 and US 522 cross Crooked Run and have a partial cloverleaf interchange with I-66 as they leave the town of Front Royal.