Top 10 Free Attractions in London

LONDON October 13, 2009 — -- Once the center of the British Empire, London remains the largest city in Europe and is home to an incredibly diverse population, as well as countless historical and cultural gems.

Unfortunately for the millions of tourists who come to visit London each year, however, the United Kingdom's capital is also one of the most expensive cities in the world. Luckily, an enjoyable trip to London does not have to break the bank.

ABCNews.com recommends 10 of the best free attractions to check out while in the city.

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One of London's classic tourist attractions and it doesn't cost a dime. At 11:30 a.m. on the dot, every day during the summer and every other day in the winter, passersby can watch through the gates of Buckingham Palace as the queen's guards, dressed in full uniform, carry out their intricate ceremony, called "Guard Mounting," set to music. Get there early for an optimal viewing position. If you love it and want to see more, check out the Guard Mounting again at Windsor Castle at 11:00 a.m.

While it may seem like just another one of London's many squares, Trafalgar Square has special significance. Since 1830 it has served as a cultural space, open to the public. The square is full of and surrounded by monuments, statues and buildings of both historical and contemporary significance. Among the most significant are a monument to the Battle of Trafalgar called Nelson's Column, and the National Gallery, which houses Western European paintings from 13th to 19th centuries.

Besides its fixed attractions, Trafalgar Square hosts cultural, educational, artistic and sporting events, as well as ceremonies and festivals throughout the year. Look up what's going on in advance, or just show up and take a picture on top of one of the giant brass lions surrounding Nelson's Column.