New Jersey State Route 33 runs east-west across Mercer County. This is the western most county that NJ St Rt 33 passes through. NJ St Rt 33 passes through the following towns in Mercer County. Trenton Hamilton Square Robbinsville Hightstown NJ St Rt 33 is multi-plexed in Mercer County. U.S. Rt. 130, from near Robbinsville to near Hightstown. NJ St Rt 33 intersects the following highways in Mercer County. U.S. Rt. 1, at Trenton. New Jersey State Route 129, at Trenton. Interstate 295, near Mercerville. U.S. Rt. 130, near Robbinsville. U.S. Rt. 130, near Highstown. Interstate 95, (New Jersey Turnpike) near Highstown. New Jersey State Route 133, near Etra.