The Oxford Cambridge Boat Race

• What: A tough rowing race, and a more than 150-year-old tradition
• When: End of March to early April
• Where: From Putney to Mortlake on the Thames River in London
• Admission: Free
• Website

A single crew from Oxford and a single crew from Cambridge have raced each other on this London stretch of the Thames for more than 150 years. It's a grueling race. The 4.25 mile distance is three times the length of an Olympic course and the Thames is not a placid stretch of water. The whole event goes back to a challenge between two school friends in 1829.

The date varies from year to year, depending upon the Oxford and Cambridge terms, and the needs of television schedulers (the race is watched by about 8 million worldwide). Tides determine the starting pistol; the race sets off an hour before high water so that the crews are always racing with the tide rather than against it.

Even if you've never watched a crew race in your life, make your way to one of the bridges or pubs along the route if you are in London on race day. You may only see the boats race by in seconds (the whole race takes about twenty minutes), but the crowds and the festival atmosphere make this a great day out.