Hindhead Tunnel

The Hindhead Tunnel, opened in 2011, is part of the 6.5 km dual-carriageway Hindhead bypass that replaced one of the last remaining stretches of single-carriageway on the 68-mile A3, the London to Portsmouth road. The bypass was constructed to improve road safety, reduce congestion and improve air quality. At 1,830 metres in length, the tunnel is the longest non-estuarial road tunnel in the United Kingdom, and takes the road beneath the Devil's Punch Bowl, a Site of Special Scientific Interest.

A naval dockyard has existed in Portsmouth since at least Tudor times, giving significant importance to the road linking that city with London. The original 73-mile route skirted the north-western limits of The Weald climbing to the summit of Gibbet Hill close to Hindhead. In 1826 the road was rebuilt around the Devil's Punch Bowl to ensure that the gradient was no more than 5%. The road became part of the A3 when road numbering was introduced in the 1920s.

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