London Millennium Tower
Foster proposed Europe's tallest building for the bombed Baltic Exchange site, but heritage objections cleared the way for the Gherkin instead.
Quick facts
- Existence state
- Never Born
- Peak stage
- detailed preproduction
- Research confidence
- high
- Last verified
What it was
An unbuilt 386-metre office tower designed by Foster + Partners for St Mary Axe in London.
The glass tower would rise in a series of curved, environmentally responsive layers above the City.
Existence timeline
Foster presents a 92-storey design.
Its height dominates discussion of London's skyline.
English Heritage argues the tower would overwhelm the capital.
The landowner withdraws from the proposal.
Swiss Re obtains the former Baltic Exchange site.
A shorter Foster design occupies the location.
Why it ended
English Heritage and planning opposition made the project untenable, and the site changed ownership.
Last confirmed trace
Models, drawings, planning studies and contemporary reporting preserve the design.
What it left behind
Its engineering and environmental ideas informed later Foster towers, while its site became 30 St Mary Axe.
How we classified it
The proposed archive unit never reached ordinary public access in the form being documented.
The strongest verified milestone maps to detailed_preproduction under Arrival Score V1.
Sources & verification
Last reviewed 2026-08-01. Sources are linked so readers can inspect the evidence directly.