When it opened on December 24, 1911, the Cut-Off was considered a super-railroad, a state-of-the-art rail line, built upon large cuts and fills, and which included two large concrete viaducts that allowed for what was considered high-speed travel at that time. The line was part of a main line between Hoboken, New Jersey, and Buffalo, New York. The Cut-Off ran west for 28.5 miles (45.9 km) from Port Morris Junction — near the south end of Lake Hopatcong in New Jersey, about west-northwest of New York City — to Slateford Junction near the Delaware Water Gap in Pennsylvania.