Morning Skip the soulless, corporate behemoths and go for a boutique experience. Try the Charlotte Street Hotel, which is brilliantly located near Covent Garden, Mayfair, and Soho and has 52 brightly colored, cozy rooms—plus a stylish drawing room where you can help yourselves to wine and fancy Scotch from the honor bar. Rooms from $495; Another gem is Blakes, in cushy South Kensington, where the 47 rooms and Opium Den lounge have a sexy, Far East feel and you may bump into Gwyneth dodging paparazzi. Rooms from $338
Afternoon When celebrities want to be seen, they head for the Wolseley—a grand café on Piccadilly Road. Airline food didn't cut it, so dig into the sublime burger.
Evening After a nap, jump a taxi to Notting Hill and share the black-cod tempura with yuzu aioli and spare ribs at E&O—it turns into a real scene at night.
Morning Lucinda Bredin, editor of The London Magazine, suggests a perfect pairing: art at the Tate Modern and a grazing lunch (baked pork pies, cheese nibbles) at the famous food emporium Borough Market.
Afternoon Tour the hottest royal attraction of 2012: Kensington Palace, Will and Kate's new home, fresh off a $19 million renovation.
Morning Visit arty Shoreditch (think Williamsburg, Brooklyn), full of cafés, boutiques, and high-profile galleries like White Cube.
Afternoon Leave hipsterville for posh Mayfair and Claridge's hotel, which serves a champagne tea that's fabulously full-on formal.
Evening Go Italian for your last night (there's loads of English yumminess to come) at the River Café in Hammersmith, where the pastas are made fresh.
Morning Pick up a rental car and drive an hour and a half northwest to the wildly picturesque Cotswolds, a 790-square-mile area of rolling emerald hills and honey-colored thatched-roof cottages. Village-and-pub-hopping has always been popular, but the area's profile has been raised in recent years thanks to famous residents like Liz Hurley, Kate Winslet, and Damien Hirst.
Afternoon Arrive in tiny Barnsley and unpack at Barnsley House, a 17th-century manor where the rooms are contemporary, not granny-floral-chintzy. Rooms from $365. There's also a sleek spa with a heated outdoor hydrotherapy pool.
Evening Enjoy a seductive dinner for two in the hotel's Roman-style temple, set in a gorgeous garden.
Morning Explore Painswick's six-acre Rococo Gardens, home to scores of roses and a swirling hedge maze à la Alice in Wonderland.
Afternoon In close-by Stonehouse, wander around Woodchester Mansion, a 19th-century house abandoned by its builders. This place is so spooky, it was on an episode of Ghost Hunters International.
Evening Try out the local ales at The Swan, a trendy gastropub in Southrop. Cotswolds homeowner Kate Moss is a regular, so wear your skinny jeans, and make sure to order the outrageous rib-eye steak.
Morning Locals—including Prince Charles, who has an estate near Tetbury—are into organic and green living. Don't miss the prince's creation, Highgrove Shop, in Tetbury town, which sells all manner of English goodies: biscuits, tea, garden gear.
Afternoon Borrow the hotel's house bikes and pedal to nearby Cirencester, an adorable village. The "in" cafe is Made by Bob, famous for its decadent pastries.
Evening Upgrade to filet of wild halibut and blood-orange soup at Michelin-starred Lords of the Manor, in Upper Slaughter. P.S.: It's also a very nice hotel. Rooms from $300.
Morning Fuel up on sausages and eggs at Barnsley House.
Afternoon Lady Mary and Matthew fans should head to Highclere Castle, just an hour away, where Downton Abbey is filmed. The grounds are even more out of hand than they are onscreen.
Evening You've seen how the aristos live. Now drive 45 minutes to Hurley and The Olde Bell, where the staff might have honeymooned. Recently redecorated (it's English via Scandinavia), this inn serves up a perfect last meal: quail and hand-cut chips (that's fries to us Yanks) for those who can still button up their jeans. From $346. Mercifully for your waistline, your next stop is Heathrow!