About HS2 South Portal & Colne Valley Viaduct School / College Visit

South Portal is the main site of the Align joint venture, working in partnership with HS2. From here, our two tunnel boring machines Florence and Cecilia were launched to dig the Chiltern Tunnels, as well as the starting point of the Launching Girder called Dominique building the Colne Valley Viaduct. This is also the largest constraction site on HS2 with 550000 square meters of land.


Visit to our Exhibition Centre where you can learn about how our tunnel boring machines work, and how we are building the longest railway bridge in the UK. With a minibus tour. This visit is PPE free.  


Bookings are currently unavailable for this site.


Address Align,
South Portal Site,
Chalfont Lane,

About HS2

HS2 is a new high speed railway linking up London, the Midlands, the North and Scotland serving over 25 stations including eight of Britain’s 10 largest cities and connecting around 30 million people.

HS2 is the UK’s flagship transport levelling up project. It is the biggest rail investment ever made in the North of England and is Europe’s largest infrastructure project.

The new high-speed line will run between the North West and the South East, stopping at Manchester, Birmingham and London with trains continuing on the existing network to Scotland ...