1 Undershaft

1 Undershaft (also called One London) is a skyscraper planned for the City of London financial district. The scheme is being developed by Aroland Holdings and designed by Eric Parry Architects. It is set to replace the St Helen's tower, and when it is built it will be the second-tallest building in London and the United Kingdom after The Shard). Despite being shorter than the Shard, One London will sit on higher ground, and the two towers will appear the same height on the skyline, due to the buildings sharing the same AOD (Above Ordnance Datum) height of 309.6 metres. The building is the third design for a skyscraper at 1 Undershaft, replacing two previous proposals designed by architects Avery Associates and Eric Parry themselves respectively. The second proposal, nicknamed 'The Trellis' due to its external cross bracing, was given approval in November 2016, but this design was ultimately discarded in favour of a quad-segmented tower revealed in August 2023. The substantial changes entailed will result in 1 Undershaft needing to once again apply for planning permission from the City of London Corporation. Construction is planned to take around five years subject to planning. In June 2026, a main contractor appointment was expected in late 2026, with construction planned to start in 2028.