1. Tower of London
Marvel at the massive Tower, which is actually several buildings, parts of which are over 1,000 years old. Its purpose has changed over time--from fortress to palace to prison--and it now serves as one of London's most favored tourist spots. See the Crown Jewels, watch historical re-enactments, take a tour guided by a Beefeater, see medieval armor and weapons, and exhibits about its many famous prisoners.
Nearest tube stop: Tower Hill
http://www.hrp.org.uk/toweroflondon
2. Trafalgar Square
Walk around Trafalgar Square, one of London's most famous sights and a favorite location for many films, rallies, demonstrations and activities. Surrounding the Square is St. Martin's-in-the-Field Church, the English National Opera and the Institute of Contemporary Art. The nearby National Portrait Gallery and the National Gallery are both free.
Nearest tube stop: Charing Cross and Leicester Square
http://www.london.gov.uk/trafalgarsquare
3. Big Ben
See one of London's most classic symbols, a giant clock known for its excellent accuracy for over 150 years. Big Ben is connected to the Palace of Westminster, where Parliament works and tourists may attend debates and committee meetings. Tours are available during the summer. Next door is Westminster Abbey, Tower Bridge and close by is where the prime minister lives.
nearest tube stop: Westminster
http://www.parliament.uk
4. Buckingham Palace
Get there early for a good view to watch the famous Changing of Guard ceremony. It starts daily at 11:30 a.m. in the summer and alternate days the rest of the year. Visit the inside of the Queen's home and office from August through September, and marvel at the extensive collection of lavish art treasures from the Royal Collection.
Nearest tube stop: Victoria
http://www.royalcollection.org.uk/default.asp?action=article&ID=30
http://www.royal.gov.uk/RoyalEventsandCeremonies/ChangingtheGuard/Overview.aspx
5. London Eye
One of London's newest and most popular destinations, the London Eye is among the largest ferris wheels in the world. The fourth tallest structure in London reaches a height of 443 feet and at its pinnacle you can see 25 miles in all directions. There are 32 glass-enclosed capsules that each hold up to 28 people. One rotation lasts 30 minutes.
Riverside Building
Westminster Bridge Road
Nearest tube stop: Waterloo
http://www.londoneye.com
6. See a Show
Relax at a play, musical, opera or dance production. The Half Price Ticket Booth ('tkts') with two locations offers amazing discounts, and tickets are available up to a week before the show. But the best prices are the day of the show.
tkts Leicester Square
http://www.tkts.co.uk
7. Piccadilly Circus
Sometimes called the "Times Square" of London, Piccadilly Circus is an intersection of five roads in the heart of London. It is an excellent place to access several popular shopping and entertainment locations and is extremely close to Soho, Chinatown and Trafalgar Square.
Nearest tube stop: Piccadilly Circus
8. Tate Modern
One of London's most popular art galleries has a massive collection of British art dating from 1500 to the present day and international art. This free gallery features numerous works by Matisse, Dali, Picasso, Warhol, Rothko, Pollock and Magritte.
Bankside, London
Nearest tube stop: Southwark, Mansion House, London Bridge
http://www.tate.org.uk/modern
9. Hampton Court Palace
Step back in time and explore the home of several royals, most famously Henry the VIII. Get lost in one of the most famous garden mazes in the world, watch cooking inTudor kitchens, explore over 60 acres of gardens and hear ghost stories of those who reportedly haunt the palace. Overnight accommodations are also available to feel like a king or queen for the night.
East Molesey
Surrey
Nearest tube stop: Waterloo
http://www.hrp.org.uk/hamptoncourtpalace
10. Harrods
Shop 'til you drop at one of the largest and most well-known luxury department stores in the world, Harrods occupies over 1,000,000 square feet. Marvel at the many luxurious items and be sure to stop by the sweets department, where curious tourists generally end up making their sole purchase. There is a memorial to Princess Diana and Dodi Fayed, the late son of Harrods' owner.
87-135 Brompton Road
Knightsbridge
Nearest tube stop: Knightsbridge and South Kensington
http://www.harrods.com