BBC: "Historic Rise of London's Shopping Centres" (or, in the case of Brent Cross...)

Link to BBC slide show

"Britain's first shopping arcade was in Mayfair, when the Burlington Arcade opened in 1819. Lord Cavendish commissioned his architect, Samuel Ware, to design a covered promenade of shops, unofficially to stop ruffians from throwing quantities of rubbish, in particular oyster shells, onto his property."