Kensington Palace

An actual royal palace - it's where Prince William lives with the Duchess of Cambridge and their two kids. Though you probably won't bump into them in the hallway, it's still a fascinating window into the lives of royals past and present. The Diana: Her Fashion Story exhibition celebrates the life and style of the 'People's Princess'.
London's Kensington Palace has been a royal residence for over 300 years. At Queen Victoria's behest, the State Rooms were opened to the public in 1899, on her 80th birthday. Since then it's been both a private residence for the royal family and a public museum.
Head up the magnificent Grand Staircase, visit the King's State Apartments, and the King's Gallery. The beautifully ornate Cupola Room, and The Drawing Room will make you feel like you're among royalty (which, of course, you are).
Afterward, swing through the Palace Gardens. Wander the shady Cradle Walk and look out upon the ornamental flowers in the Sunken Garden. It's a great opportunity to practice your royal wave.