The annual event, which this time marks its 26th year, is organised by the Kenilworth Rotary Club and will see 2,500 competitors run 10k between the castles in Warwick and Kenilworth on June 8.

Entries are already flooding in on the website which, for the first time, allows runners to apply and pay for places online.

Leamington solicitors Blythe Liggins and Warwick's Opus 40 Business Park, which is currently under development on the old IBM site in Warwick, are again sponsoring the race.

Robert Kelly of Kenilworth Rotary Club said: "The Two Castles continues to attract top rate runners as well as local people stretching themselves in a personal challenge.

"Bringing in this latest timing technology enables runners to get their exact finishing times, which is already proving to be an incentive and we have already received hundreds of applications so far."

Richard Thornton, at Blythe Liggins, who are sponsoring the run for the third year, added: "It's fantastic to be involved with this event. Kenilworth Rotary Club works tirelessly to achieve a day which is memorable for all concerned and which raised £50,000 for charities last year."

Richard Smith of Opus Land, the company responsible for the new 260,000 sq ft business park on the old IBM site, said: "We are delighted to again be associated with this prestigious event, which brings together a passion for sport and the opportunity to raise a tremendous sum for charity."

The entry fee is £15, to include a t-shirt and medal for all finishers.

Applications can be made on line by visiting www.kenilworthrotary.org.uk. Application forms are also available from the Kenilworth Weekly News offices on Warwick Road, local libraries and fitness centres in Kenilworth, Leamington and Warwick and Blythe Liggins Solicitors on Rugby Road.