Sleepers made from old bottles, food packaging and other unwanted plastics have been installed on Britain’s mainline railway for the first time.
Network Rail said the use of recycled materials in Wiltshire will help it achieve its ambition of reaching net-zero carbon emissions by 2050.
Sleepers, which hold up rails and keep them the correct distance apart, are normally manufactured from concrete or wood.
The composite version will have a longer service life and reduced maintenance, Network Rail said.
They are designed to be used for 50 years as they do not split, rot or degrade, and can resist water, oil, chemicals and fungi.
Rail minister Chris Heaton-Harris said: “I am proud to see such a positive innovation being used for the first time on the mainline railway.
“Not only are these sleepers made from locally-sourced plastic waste, they need less maintenance and will last longer, underlining our commitment to create a greener, cleaner and more efficient rail network.”
The sleepers were recently installed across Sherrington Viaduct, between Salisbury and Warminster.
Network Rail’s Wessex route director Mark Killick commented: “This is an exciting development. Use of these recycled sleepers on the Network Rail Wessex route is a first for the overground railway network in Britain.
“Rail is already one of the greenest ways to travel, but we’re committed to even greener and better journeys whether this be changing how we maintain the lineside or finding innovative ways to improve the railway by reusing materials and reducing landfill.
“By using these sleepers, not only are we upgrading the track for customers, they will be travelling on a railway laid using sustainable materials as part of the circular economy.”