1. Euston Arch
Built in 1837 as an elaborate entrance to Euston station, the imposing Euston Arch (yes, it’s technically more of a gateway than an arch) was torn down in 1962 at the request of the British Transport Commission, after several years of extended hoo-hah and planning around redeveloping the station. Three decades later, historian Dan Cruickshank got on the case and found out that the stones from the Arch had been used to plug up the Prescott Channel, which feeds into the Lea river. Most of the stones have since been removed, and some are on display in the Doric Arch pub outside Euston station.
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