HS2 in Hertfordshire
HS2 in your area
The railway clips the south-eastern edge of Hertfordshire. It runs in deep tunnels as it moves between the London tunnels and the Chiltern tunnel.
What we're building
Colne Valley viaduct
The Colne Valley viaduct stretches for more than 2 miles (3.4km), crossing a series of lakes and waterways between Hillingdon and the M25.
Read about the HS2 works and developments taking place in Hertfordshire
Chilterns chalk grassland
The western slopes of the River Colne valley are dedicated habitat creation sites. We’re creating more than 90 hectares of chalk grassland alongside new woodland, wood pasture and wetlands — including almost 65,000 trees and shrubs of 32 species and nearly 2 miles (3.5km) of new hedgerows.
Read about the HS2 works and developments taking place in Hertfordshire
Chiltern tunnel (south portal)
The Chiltern tunnel is the longest tunnel on the HS2 route, stretching 10 miles (16km) beneath the Chiltern Hills.
Read about the HS2 works and developments taking place in Hertfordshire
How we manage construction
We work to minimise disruption for residents and businesses, reduce the impact on roads and transport, protect the environment, and keep communities informed at every stage.
Current work in the area
HS2 works near you
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