Network Rail, the UK infrastructure agency, is beginning a programme of works on the 144-year-old Ribblehead Viaduct, the key link on the Settle-Carlisle Line. The huge viaduct carries freight and passenger traffic through the north of England, and provides an alternative to the busy West Coast Main Line. Although the Settle-Carlisle route has been threatened with closure in recent decades, it is destined to play an increasingly important role as HS2 traffic demands future capacity on the West Coast.