Organisers expect about 250,000 people over the next five days.

The annual rowing competition takes place over a stretch of the Thames, just under a mile-and-a-half in length, on the border of Berkshire and Oxfordshire.

Top British Olympic rowers Matthew Pinsent and James Cracknell are expected to take part again in the five-day event.

The regatta operates a knock-out draw with only two boats racing in each heat, which entails the organisation of up to 100 races on some of the five days.

Organisers are expecting a total of about 250,000 people to attend the regatta.

In its 154-year history the regatta has often been honoured by visits of members of the Royal Family, of which the most recent was The Princess Royal in 1999.