Growth in Britain is very fast, with the tallest tree, at Benmore in southwest Scotland, reaching 56.4 m (185 ft) in 2014 at age 150 years,[39] and several others from 50–53 m (164–174 ft) tall; the stoutest is around 12 m (39 ft) in girth and 4 m (13 ft) in diameter, in Perthshire. The Royal Botanic Gardens at Kew in London also contains a large specimen. Biddulph Grange Garden in Staffordshire holds a fine collection of both Sequoiadendron giganteum and Sequoia sempervirens (coast redwood).