South Devon Banks

The South Devon Banks are a series of steep inclines on the ex-GWR railway line linking Exeter and Plymouth in Devon, England. These two cities are separated by the rocky uplands of Dartmoor forcing the early railway surveyors to propose that the line skirt the difficult terrain of the comparatively sparsely populated moorland. Isambard Kingdom Brunel, in surveying the South Devon Railway, opted to push a line along a coastal strip between the Exe and Teign valleys, and then to climb the southern outliers of Dartmoor making for the head of the Plym estuary. From Newton Abbot, the line climbs Dainton Bank, and from Totnes it climbs Rattery Bank, reaches a peak at Wrangaton summit, and then descends Hemerdon Bank to reach Plymouth. These three are collectively known as the South Devon Banks.

The third steepest main line bank on the British mainland, with 2 miles varying between 1 in 36 and 1 in 57. Leaving Newton Abbot station, the line is near level until Aller Junction, where the line to Torbay diverges to the left. The climb proper begins at Stoneycombe, where there was a signal box and quarry siding, and continues through Dainton tunnel to Dainton signal box, a distance of 2 miles and 17 chains (3.56 km).

The seventh steepest main line bank on the British mainland, with a constant 4 ¹⁄₄ miles (6.8 km) initially between 1 in 45 and 1 in 70 before easing to 1 in 90 and then increasing to 1 in 65. Leaving Totnes station, the line immediately climbs past the site of Tigley signal box and on to the site of Rattery signal box, a distance on 4 miles and 50 chains (7.44 km).

The fourth steepest main line bank on the British mainland, with a constant 1 in 42 for 2½ miles. The climb begins at Plympton and climbs all the way to Hemerdon signal box, a distance of 2 miles and 50 chains (4.22 km).

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