Roseville Tunnel is a 1,024-foot (312 m) two-track railroad tunnel on the Lackawanna Cut-Off in Byram Township, Sussex County, New Jersey. The tunnel is on a straight section of railroad between mileposts 51.6 and 51.8 (83 km), about 6 miles (9.7 km) north by northwest of Port Morris Junction. Operated for freight and passenger service from 1911 to 1979, it is undergoing work intended to return it to passenger service by 2026.