Why is it that the ornamental pediment on the building to the left of the picture almost exactly mirrors the iconic pediment of this red telephone box?
Though a mere shell, no longer maintained and no longer serving any useful purpose, Giles Gilbert Scott's classical modernist masterpiece stands as a symbol of 20th-century London design the world over.
But enough about Battersea Power Station (hah!)--Scott was also responsible our famous red telephone boxes, and this one here is an original K2, designed in 1926.
Scott was a trustee of Sir John Soane's museum, and would have been intimately familiar with Soane's work, both here in Dulwich, and at St. Pancras where he built his own family mausoleum.
The normal version of the story is that the phone box pediment was inspired by the St Pancras mausoleum, but it is a much better match for this one. In this mausoleum tower, one can even make out analogues to the "telephone" placard and the K2's square-glazed windows.