Built to accommodate a single line, a section of Farnley Scar Tunnel (Bridge No.70) gave way on 28th December 1844 during widening work for double track operation. It had opened nine years earlier after more than one million bricks had been laid. A further £1,000-worth of repairs were ordered in 1871 when an inspection uncovered weaknesses.

This chequered history led to the tunnel’s eventual abandonment. Between November 1959 and June 1962, a deviation line was laid through a new cutting under the instruction of Arthur Dean, then Chief Civil Engineer of BR’s North Eastern Region.

Farnley Scar Tunnel was taken out of service on 27th May 1962. Plans to backfill it were recently abandoned by Network Rail on the grounds of cost.