|Location Map ( geo)|
|Transport for London|
|A301 • A4200|
The Strand Underpass permits northbound traffic on the A301 Waterloo Bridge to avoid the junction with the A4 Strand, passing beneath the Aldwych and resurfacing northbound on the A4200 Kingsway. It was originally a tram tunnel, the southern part of which was converted to a one-way road tunnel in 1964.
The tunnel's roof is well below standard overhead clearance and the Underpass is signposted with a height restriction of 11'0" (3.3m).
Traffic in the single-lane tunnel runs northbound only, in order to reduce traffic conflicts at the junction of Waterloo Bridge, Strand and Aldwych.
Travelling north on Waterloo Bridge, direction signs indicate that both lanes continue forward, signposted "Strand" and "Aldwych", while a new lane forms on the right, signposted "Kingsway only" and with a mandatory height restriction. The use of street names on direction signage is unusual and generally discouraged; one might normally expect to see, for example, "Trafalgar Square" and "City" for the left lanes, and "Holborn" and "Euston" to the right.
The right-hand lane of the bridge then divides, forming a new third lane. Shortly afterwards this is separated from the rest of the roadway by kerbing and thus becomes a third carriageway in the centre of the bridge. The width of both the northbound and southbound carriageways is reduced to make space for the new third carriageway; northbound the separate bus and cycle lanes merge to form one narrow bus lane, while southbound there is one wide general traffic lane and a cycle lane on this section.
Several automatic over-height vehicle warning signs exist here and are often switched on unnecessarily - notably for several years around 2008 just before the underpass was refurbished. Because of this, even when they are activated, they are routinely ignored by traffic. There is also a barrier, kept parallel to the direction of travel but which can be swung out to block the road, in case the tunnel is closed.
The centre carriageway begins to drop steeply at the point Waterloo Bridge reaches the north bank, descending between tiled walls, and enters the tunnel while still descending. There is a definite right turn, just as the roadway levels off, before the tunnel assumes the more gentle rightward curve of the Aldwych. It then turns very sharply left to join the line of Kingsway - this corner only really being safe at 15 or 20mph - and immediately afterwards emerges into daylight and begins a steep climb between retaining walls.
The road emerges in the middle of Kingsway between railings, and eventually forms the right-hand lane of three. The first set of traffic lights after leaving the Waterloo roundabout at the south end of the bridge is shortly afterwards at the crossroads with Remnant Street.
The original underpass was constructed as an integral part of the project that created Kingsway and the Aldwych in the early 20th century. These two new streets were cut through an area of slum clearance, and many smaller streets have vanished underneath the new development.
As originally built, the underpass carried two tram tracks, enabling two-way running, with access at the northern end near the junction of Theobalds Road and Southampton Row, where a cobbled ramp with tram tracks still in situ desccends into the middle of Kingsway. This leads to the northern section of the route which is normally a store for Camden Borough Council's highways department but which, at the time of writing, has been temporarily requisitioned as a worksite for Crossrail.
At its southern end, the underpass stayed underground, travelling under the northern approach to Waterloo Bridge and emerging onto the Embankment underneath one of the bridge's arches. From the Embankment this access is visible as a large gated opening in the wall under the bridge.
The underpass was notable for including an underground tram station beneath Kingsway, on the section between Aldwych and Remnant Street.
When trams ceased running in London in the early 1950s, the tunnel became disused. The installation of the modern underpass required significant changes, including two openings being created in the tunnel roof and new ramps being inserted. The vehicle underpass as it exists now does not use the full former tunnel line and a significant part of the tram underpass still exists at the northern end.
- Subterranean Britannica article on its former use as a tram tunnel
- CBRD Video of the Strand Underpass (archive.org)