Toldish Tunnel was built by Joseph Treffry as part of his mineral tramway from Newquay (Newquay to St. Dennis) which opened in 1849. This line was built to carry trams. In 1874 the line was taken over by the Cornwall Minerals Railway and the line from Newquay was extended to Par railway station. At this time the line from Newquay to Par was converted to standard gauge which was needed for the larger passenger carrying trains. It was not viable to widen the tunnel, so in 1874 it was bypassed and closed. The new line missing out the Toldish tunnel section was opened on 1 June 1874.