Strand Underpass the former Aldwych tramway station: because of the greater width requirement, 27 trees and some pavement were removed for it to be constructed. The tunnel is used by the 521 bus route northbound. In 2012, the direction of traffic in the tunnel was temporarily reversed, so that it was in use by southbound traffic. This was to facilitate easier traffic flow during the 2012 Summer Olympics. Strand Underpass The Strand Underpass is a one-way vehicle tunnel in central London connecting Waterloo Bridge to Kingsway near Holborn. Opened in 1964, it was built within the former Kingsway tramway subway, which closed
London Bridge Greater London Authority. The crossing also delineates an area along the southern bank of the River Thames, between London Bridge and Tower Bridge, that has been designated as a business improvement district. The abutments of modern London Bridge rest several metres above natural embankments of gravel, sand and clay. From the late Neolithic era the southern embankment formed a natural causeway above the surrounding swamp and marsh of the river's estuary; the northern ascended to higher ground at the present site of Cornhill. Between the embankments, the River Thames could have been crossed by ford when the tide was low,