North Downs Tunnel

North Downs Tunnel
North portal, with Class 373 on Eurostar service heading to Paris
Overview
Other name(s)Blue Bell Hill Tunnel
LineHigh Speed 1
LocationBlue Bell Hill, Maidstone, Kent
Coordinates51°19′44″N 0°30′21″E / 51.32890°N 0.50589°E / 51.32890; 0.50589
Operation
Work begun1999
Opened2001
OwnerNetwork Rail
North portal, dust whipped up by a test train before opening in 2003
South portal, leading under the North Downs at Blue Bell Hill

The North Downs Tunnel, also known as the Blue Bell Hill Tunnel, is a railway tunnel that carries High Speed 1 through the North Downs, at Blue Bell Hill near Maidstone in Kent, south-east England.

The tunnel is 3.2 kilometres (2 mi) long,[1] with an internal diameter of 12 metres (40 ft) and a cross-sectional area (CSA) of 150 square metres, and descends to a depth of 100 m (325 ft) below the chalk hills. Thus, at the time of its completion, the North Downs Tunnel was both the largest (in terms of CSA) and deepest twin-track railway tunnel to have ever been constructed in the UK.[2] Trains using High Speed 1 can reach 300 kilometres per hour (186 mph) whilst in the tunnel.

  1. ^ "HS1 Sectional Appendix" (PDF). High Speed 1. May 2013. p. A19. Retrieved 6 February 2022. NORTH DOWNS TUNNEL (3199m)
  2. ^ Cite error: The named reference arup summ was invoked but never defined (see the help page).