When it opened in 1960, this U.S. Embassy designed by modernist starchitect Eero Saarinen was London's first purpose-built embassy. All the others were located in historic buildings or grand mansions. The nine-story building (three stories are below ground) with its distinctive stone fenestration and enormous golden eagle up top was controversial when it first opened on an entire block of Mayfair's tony Grosvenor Square just one year before Saarinen died in 1961. Modernism had not yet taken hold in Britain, and its neighbors were all Georgian landmarks. The embassy's size was also a point of contention: it is still the largest U.S. embassy in Western Europe.
The building, which is Saarinen's only work in Britain, has a striking Venetian-inspired design; the architect kept a picture of another ornamental monolith, the Doge's Palace in Venice, pinned up to his drawing board. Since its rough debut, the building has evidently grown on its host country (it is one of the few embassies not on American-owned soil, as an English Duke was being fussy when it came time to sign the lease), and was listed as a monument in 2009. Saarinen's embassy is still in use, but not for much longer.
Serious security issues were raised in 2008, along with a giant barrier despised by Londoners, and an announcement was made that a new embassy would be built across town by the Philadelphia firm KieranTimberlake. The current embassy's site, which has been valued at £500M ($780M), has already been sold to Qatar. However, the Grade II-listed building's future developers will have to maintain Saarinen's intriguing (if not particularly beloved) design. More photos, below: