St Pinnock Viaduct

St Pinnock Viaduct is a railway viaduct built between 1854 and 1855 by Isambard Kingdom Brunel, and it was heightened in 1882. The structure features seven piers made of roughly dressed, coursed slatestone sourced from Westwood quarry, spaced approximately 60 feet apart. Each pier consists of eight buttresses with weatherings that rise to form five stages, with pointed openings in the upper four stages. The piers have a slight batter of about 1 in 100. In 1882, the piers were raised with a slightly cruder, tapering sixth stage, and iron girders replaced Brunel's original timber trestles. The viaduct originally supported a two-track railroad in 1882, which was later carried on riveted plate steel girders with steel guardrails and refuges on the north side. The viaduct measures 633 feet in length and stands 151 feet tall, making it the tallest viaduct in Cornwall. It is part of a series of viaducts built in quick succession along Brunel's Plymouth to Truro Great Western Railway line, which opened in 1859.