Best of Olympic Games - free

The Olympic Games are fast approaching and travellers will be planning itineraries with an extensive list of London's most popular tourist attractions and must-sees.

However, sightseeing can quickly become costly when you add the entrance fees, ticketing charges and transport.

Flight Centre has put together its top tips to keep travellers busy in London, without breaking the bank.

MARATHON AND ROAD CYCLING RACES

Marathons and road cycling races during the Games don't require tickets and can be watched free. Taking place in early August, both events begin and finish on The Mall, near Buckingham Palace. Grab your fix of sporting history without the hefty price tag.

ST PAUL'S CATHEDRAL AND WESTMINSTER ABBEY

Both are huge attractions in London and are known to welcome visitors to their evensong services free of charge. This is a great opportunity to witness the amazing architecture on display, not to mention a chance to marvel at the beauty of the cathedral where Kate and Wills tied the knot.

ART GALLERIES

National art galleries Tate Modern and Tate Britain offer free entry except for special exhibitions. Open daily with free guided tours and interactive zones, this is a fantastic way to spend a rainy day.

Tate Modern has a collection of 60,000 works and a cafe offering wonderful views of the Thames, and Tate Britain offers one-hour tours and 15-minute talks on painters and paintings.

BROWSE THE AISLES AT HARRODS

The world's most famous department store stretches over seven floors and 330 departments - you can get lost in Harrods for hours. The famous food hall alone is enough to keep you occupied. Pick up a few nibbles, pack your own picnic and head to the park for a leisurely afternoon.

CHANGING THE GUARD

Get your hit of royal tradition with a visit to Windsor Castle. You can watch, free, the splendid guards as they march up High St and into the castle.

If you want to witness the actual "changing" ceremony, however, you must pay the entry fee that gets you into the castle grounds.

MARKETS

Camden and Portobello markets offer everything from antiques to fresh produce and are a must for anyone who enjoys wandering between stalls.

For all the foodies out there, head to Borough Market. It's one of the top attractions south of the river, with a huge range of everything edible.

COVERAGE AT HYDE PARK, VICTORIA PARK AND TRAFALGAR SQUARE

With giant screens, state-of-the-art technology and concert-quality sound systems, these public sites with be among the best places in London to watch the Games. As well as promising live coverage, there will be have-a-go sports sessions, music and outdoor arts and entertainment.