The A122 Lower Thames Crossing would connect to the A2 and M2 in Kent to the A13 in Thurrock and junction 29 of the M25 in the London Borough of Havering. 

It would be approximately 14.3 miles long, with 2.6 miles of this in two tunnels under the Thames – making them the longest road tunnels in the UK. The tunnels would be located to the east of the village of Chalk on the south side of the Thames, and to the west of East Tilbury on the north side.