Geograph - photograph every grid square

The recently reconfigured track layout, known as the Werrington Grade Separation Plan, is seen here from the bridge at the junction with Lincoln Road and Hurn Road on the outskirts of Werrington. The plan involved the construction of a new connection between the Stamford Lines and the Great Northern Great Eastern (GNGE) line.
Hitherto, trains joining or leaving the GNGE here were obliged to cross the East Coast Main Line (ECML), resulting in delays and bottlenecks. The Grade Separation Plan provided for a new three-kilometre line including an underpass (or "dive under") enabling trains to pass underneath the ECML. The tracks which pass through the "dive under" can be seen on the left-hand side of the image rejoining the existing Peterborough to Lincoln section of the GNGE line at Glinton Junction, as it is designated by Network Rail from the name of the neighbouring village.
Work on the project, which cost a total of £200 million, commenced in the summer of 2018. The tunnel itself was created in January 2021 by pushing a curved concrete box weighing in excess of 11,000 tonnes and measuring 510 feet (155 metres) in length under the ECML with the aid of hydraulic jacks. The tunnel had been prefabricated in nine separate sections prior to installation. This represented the first time that this particular construction technique had been employed in the United Kingdom.
The "dive under" - which formed part of a £1.2 billion upgrade of the ECML - was formally inaugurated by the then Minister of State for Transport Chris Heaton-Harris on December 9th., 2021.

Sources: Link
Link
Link
Link
Link