New pictures have been published which reveal the progress of the UK's longest railway bridge.

HS2 has updated the public on the construction of the Colne Valley Viaduct, which will carry trains between of HS2's London and Chiltern Hills tunnels at up to 200 miles per hour.

Watford Observer: Aerial view of HS2's Colne Valley Viaduct at sunset.Aerial view of HS2's Colne Valley Viaduct at sunset. (Image: HS2 Ltd)

The viaduct will span the Grand Union Canal, River Colne, local roads, and several lakes once completed, earning it the title of Britain's new longest rail bridge at 2.1miles long.

New photos show connected segments of the viaduct stretching over a series of lakes.

Watford Observer: Aerial view of HS2's Colne Valley Viaduct at sunset.Aerial view of HS2's Colne Valley Viaduct at sunset. (Image: HS2)

Construction of the viaduct passed the high-way point in November after it installed more than 500 of the Colne Valley Viaduct's 1,000 deck segments.

Weighing up to 140 tonnes each, each section is uniquely shaped to allow the structure to gently curve as it carries the railway over land, lakes and the Grand Union Canal.

Watford Observer: Aerial view of HS2's Colne Valley Viaduct at sunset.Aerial view of HS2's Colne Valley Viaduct at sunset. (Image: HS2)

Construction of the viaduct began in December 2021 and is expected to be completed by summer 2025.

A launching girder lowers each segment into place as it moves south across the valley, forming 56 piers which will stretch across land and water.