U.S. Federal Route 1 is a north-south highway in Mercer County. It runs along the Trenton Freeway. U.S. Rt. 1 passes through the following towns in Mercer County. Trenton Penns Neck U.S. Rt. 1 is not multi-plexed in Mercer County. U.S. Rt. 1 intersects the following highways in Mercer County. New Jersey State Route 29, at Trenton.
Branches of U.S. Rt. 1 in Mercer County. A guide sign near Princeton Junction. A BGS near Princeton. A BGS on WB Meadow Road. NB U.S. Rt. 1 south of Meadow Road. A BGS on Meadow Road. A guide sign on SB U.S. Rt. 1. SB U.S. Rt. 1 north of Quaker Bridge Road. NB U.S. Rt. 1 at Quaker Bridge Road. A guide marker at Quaker Bridge Mall. A BGS on NB U.S. Rt. 1. SB U.S. Rt. 1 south of Quaker Bridge Road. SB U.S. Rt. 1 at Quaker Bridge Mall. A guide sign on the service road from NB U.S. Rt. 206 to Franklin Corner Road. SB U.S. Rt. 1 at I-295. A BGS on NB I-295. A set of BGS's on the ramp from SB I-295. NB U.S. Rt. 1 at I-295. NB U.S. Rt. 1 near Shipetaukin Creek. SB U.S. Rt. 1 south of Franklin Corner Road. SB U.S. Rt. 1 north of BUSN U.S. Rt. 1. A guide marker on SB BUSN U.S. Rt. 1. A BGS on WB I-195. A BGS on NB NJ St Rt 29. A BGS on SB NJ St Rt 29. A BGS on SB NJ St Rt 29. SB U.S. Rt. 1 at the Delaware River.
