Work No. 4L—U.K.A passenger subway commencing in St. Pancras Station at a point 75 metres west of the junction of Pancras Road with Euston Road, passing south-eastwards beneath Euston Road and terminating in the footway on the southern side of Euston Road at a point 75 metres south-west of that road junction, including a junction with the new ticket hall (part of Work No. 4K) and a permanent opening in Euston Road at that termination;