A TOTAL of 5,500 competitors will swim, bike and run in the beautiful surroundings of Blenheim Palace this weekend as the fourth annual triathlon comes to the county.

The Blenheim Triathlon attracts entrants from across the UK, and tens of thousands of pounds are raised each year for charity.

The sport is growing hugely and the success of local athletes such as Sophie Whitworth, who won a silver medal at the World Championships last year, and Emma-Kate Lidbury, who took gold in the European Championships last month, has seen the ranks swell at Oxford Triathlon Club in recent years.

Club chairman Sean Nicolle said: "Our membership has increased hugely in recent years - from 80 in 2004 to 220 now.

"Some of that is down to Blenheim in particular, but also the take-up of the sport in general is increasing.

"We always welcome new members to the club and have a real range of abilities, from people who have recently won a gold medal in the European Championships to novices waiting to take part in their first triathlon."

The club has been holding open water sessions at Cassington Gravel Pits to help novice competitors prepare for Blenheim this weekend.

Amy Brighton, 27, of Oxford, was one of the open water novices to attend a session on Saturday.

She said: "I'm doing my first triathlon at Blenheim.

"It just looked lots of fun so I thought I would give it a go.

"Swimming in a lake is a bit different to what I thought - especially with so many people around you.

"But once I got into it, it wasn't too bad.

"I am a bit nervous, but I am looking forward to the cycling section."

The Blenheim Triathlon isn't just for adults, and an event has been organised to encourage children to be more active.

The Kid's Zone hosts fun competitions for children over the age of three alongside the main triathlons.

The Kid's Zone events take place at 10am, 12.30pm and 3pm on both days so parents can fit their children's events around their own.

Entry costs £10 and every child will be given a medal for their efforts at the end.

Children wishing to take part will need to bring their own bike and helmet, which will be checked for safety before the race.

For more information see www.theblenheimtriathlon.com/BTKidsZone