This curvaceous thoroughfare was conceived by John Nash and his patron, the Prince Regent -- the future George IV -- as a kind of ultracatwalk from the Prince's palace, Carlton House, to Regent's Park (then called Marylebone Park). The section between Piccadilly and Oxford Street was to be called the Quadrant and lined with colonnaded shops purveying "articles of fashion and taste," in a big PR exercise to improve London's image as the provincial cousin of smarter European capitals. The scheme was never fully implemented, and what there was fell into such disrepair that, early this century, Aston Webb (of the Mall route) collaborated on the redesign you see today. It's still a major shopping street. Hamleys, the gigantic toy emporium, is fun; and since 1875 there has been Liberty, which originally imported silks from the East then diversified to other Asian goods, and is now best known for its "Liberty print" cottons, its jewelry department, and -- still -- its high-class Asian imports. The mock-Tudor interior, with stained glass and beams taken from battleships, is worth a look. Tube: Piccadilly Circus or Oxford Circus.