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Buckinghamshire tunnels

Buckinghamshire will benefit from two HS2 tunnels, carrying the railway from the Colne Valley to Wendover - the Chilterns tunnel and the Wendover tunnel.

A annotated map showing the HS2 line of route through Buckinghamshire and the location of the tunnels on it.

The Chilterns tunnel

The Chilterns tunnel is the longest tunnel on the route. The twin-bore tunnel is 10 miles long and will carry passengers under the Chiltern Hills. Two tunnel boring machines, Florence and Cecilia, will be used on this part of the route.

The two enormous 2,000 tonne machines – named Florence and Cecilia – will now be meticulously reassembled, tested and commissioned, by an expert team of tunnelling engineers, before they start work on the high speed rail project’s first tunnels.

The 10-mile-long ‘twin bore’ Chiltern tunnel will be the longest on the project, the first to start construction, with the TBMs set to be underground, working 24/7 for more than three years.

Chilterns tunnel location map

Follow the Chilterns tunnel TBMs on their journey from factory to site.
An aerial view of the South Portal construction site for the Chliterns tunnel.
Looking along the line of route at ground level towards the tunnel head wall where the portals will be excavated.
The tunnel head wall with side walls under construction for the entrance roof
1. An aerial view of the South Portal construction site of the Chilterns Tunnel. 2. Buttresses will support the tunnel entrance roof. 3. Preparing the tunnel boring machine launch pad.

The Wendover tunnel

Wendover tunnel is a green tunnel is a tunnel located to the west of Wendover just under one mile in length. This is a ‘cut and cover’ tunnel meaning that a cutting is created in the ground, a tunnel ‘box’ is constructed within the cutting and then the space around the box is filled to create an area of land on the surface.

Wendover tunnel location map