Netherton Tunnel Branch Canal, in the English West Midlands, is part of the Birmingham Canal Navigations, (BCN). It was constructed at a 453–foot elevation, the Wednesbury or Birmingham level; it has no locks. The total length of the branch canal is 2.4 miles (3.9 km) and the canal tunnel is 9,081 feet (2,768 m) long.
https://en.wikipedia.org/wiki/Netherton_Tunnel_Branch_Canal