HS2 has installed the final viaduct over the M6 near Chelmsley Wood, completing a major stage of construction on the high-speed railway.

The 4,750-tonne steel structure was moved into place on Saturday, October 24, using powerful hydraulic jacks to push it over the motorway near junctions 4 and 4a.

The work was carried out while the M6 remained open to traffic, helping to minimise disruption for drivers.

The latest milestone means both HS2 viaducts crossing the M6 are now structurally complete.

The two 320-metre-long structures will carry high-speed trains in different directions.

The newly installed west viaduct will carry trains towards Birmingham city centre, as well as destinations further north, including Manchester, Liverpool and Glasgow.

The east viaduct, completed in 2025, will carry trains towards London's planned HS2 stations at Old Oak Common and Euston.

The viaducts run alongside each other, supported by concrete pillars, and will eventually connect to raised sections of railway on either side.

Engineers working for HS2's construction partner, Balfour Beatty VINCI, took just nine hours to move the final section of the west viaduct into position.

During that time, the 76-metre section was moved forward using specialist equipment, at an average speed of 12 metres per hour.

Ian Clarke, senior project manager at HS2 Ltd, said: "These viaducts straddle some of the busiest sections of motorway in the country, which is why we adopt innovative techniques that allow construction to continue without closing the carriageway whenever we can.

"We have made great progress this year and I thank motorists and local communities for their patience."

Although the M6 stayed open throughout the work, the M42 M6 link road was temporarily closed to keep drivers away from the construction area.

The link road reopened at 9pm on Saturday, October 24, 25 hours ahead of schedule.

Russell Luckhurst, the Balfour Beatty VINCI engineer leading the project, said: "Two neighbouring viaducts that run parallel to each other now span the busy M6 motorway near Chelmsley Wood, after the west deck was safely and successfully moved into its final position over the weekend.

"It's a huge moment for Balfour Beatty VINCI and HS2, concluding a major programme of work above the M6 – in extremely challenging weather conditions."

More HS2 work planned near the M42

Elsewhere, strong winds forced HS2 to postpone work installing safety barriers along the Water Orton viaduct above the M42.

The work has been rescheduled for the following weekend, meaning further motorway closures are planned.

The M42 will close northbound between junctions 6 and 9 and southbound between junctions 9 and 7 from 9pm on Friday, October 30, until 5am on Monday, November 2.

Looking ahead to 2027, HS2's next major motorway project will focus on a structure known as the triple box, which will carry four railway tracks over the M42 near Coleshill.

HS2 is working with National Highways to agree when that work will take place.