If you feel the urge to escape the flurry of central London, hop the Tube north for an afternoon spent in the snug shelter of Regent's Park and Hampstead. A leisurely stroll along these peaceful streets, with gorgeous Georgian architecture and equally gorgeous inhabitants, will provide a taste of how laid-back (albeit moneyed) Londoners live. A longtime rendezvous of literati, these city districts contain two leafy parks, a handful of important historical sites, and some of the most stunning town-house architecture in the world (think any Merchant Ivory film). Excellent bookshops, contemporary boutiques, and cozy cafés line tree-shaded blocks abuzz with locals: you won't find souvenir stands here.