Editing Kingsway tramway subway (section)

===1902–1905: Construction===
The [[London County Council]] had for many years wanted to connect its "North Side" and "South Side" tramway networks in order to be able to send "North Side" trams for overhaul to the Central Repair Depot at [[Charlton, London|Charlton]] in South East London. In 1902, it decided to build a subway from Theobalds Road in the north to the [[Victoria Embankment|Embankment]] underneath [[Waterloo Bridge]] to the south, from where a surface line would continue over the bridge. Legal problems delayed permission to build the subway and tram route and it was not until 1906 that permission to build was granted, and then not to cross the bridge. Because of a sewer at the northern end and the [[District line|District Railway]] to the south it was decided to build the subway for single-deck trams only. After leaving the subway at the south end, trams turned right along the Embankment to [[Westminster Bridge]] or left on a service from [[Bloomsbury]] to the [[Hop Exchange]]. This latter service was short-lived and the tracks were removed in 1930.

The approach from the north near [[Southampton Row]] was a {{convert|170|ft|m|adj=on}} open cutting with a 1 in 10 (10%) gradient. The tracks passed through [[cast iron]] tubes underneath the [[River Fleet|Fleet sewer]] before rising slightly to enter [[Holborn tramway station]]. South from here the subway was built with a steel roof to [[Aldwych tramway station]] and, because it was not initially planned to run a public service south of here, the tracks leading towards the Strand were used as a depot with appropriate equipment and inspection pits.

In the parliamentary session of 1905, plans were submitted for an additional station at the south end of the tunnel, under Wellington Street. The opening of the new tramway along the Embankment meant it was decided to link up with this route instead and the station was never built. A new sharp curve was built under Lancaster Place to enable an exit through the western side wall of [[Waterloo Bridge]] and a triangular junction with the through line was constructed. The eastern side of this junction, leading to [[Blackfriars, London|Blackfriars]], was removed as part of the 1930s upgrade.