Wellington Bank, Somerset

Wellington Bank is a steep railway embankment and associated climb located on the Bristol to Exeter line, that climbs from just northeast of Wellington, Somerset until its peak at Sampford Arundel, where it enters Whiteball tunnel and travels under the Blackdown Hills.

The Bristol & Exeter Railway was authorised by act of Parliament in 1836, following quickly on the 1835 act for construction of the Great Western Railway. Bristol merchants were anxious to secure a railway route to Exeter, which was an important commercial centre, and which had a harbour on the south coast, in the English Channel. Coastal shipping from the South coast and from continental Europe making for Bristol needed to navigate the hazardous north Cornwall coast after negotiating the waters round Land's End.

Isambard Kingdom Brunel was appointed engineer, and his assistant William Gravatt surveyed the route in 1835 and was resident engineer for the section between Bristol and White Ball, with William Froude supervising the section from Whiteball to Exeter. Brunel himself was in charge of the design of White Ball tunnel.

The first 7 ft (2,134 mm), broad gauge, section of the line was completed to Bridgwater on 14 June 1841, and the extension to Taunton in July 1842 – both using trains leased from the Great Western. At Norton Fitzwarren just west of Taunton, the intention was to split the railway three ways:

From Creech St Michael westwards, the B&ER had followed the gently following valley of the River Tone. But just east of Wellington, the river moved further west up the steep sides of the Blackdown Hills. Brunel choose to follow a smaller valley eastwards, and pass under the Blackdown's further west, through a place called White Ball, a hill made up of easy to dig white sandstone (NB: next to it is Red Ball, a hill of red sandtone). This route would reduce the need for additional tunnelling, and allow connection with and traffic from Wellington. However, the choice also meant the construction of a long inclined bank, with a tunnel at its peak.

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