More than 10,000 people are likely to take on a gruelling assault course through the grounds of a stately home this May.
The Rat Race Dirty Weekend takes place at Burghley House, near Stamford, on Sunday, May 9.
Thousands of runners, many from Rutland, will take on the course before winding down at an after party.
So far more than 6,000 people have signed up to take on the obstacle course, which covers either 13 or 20 miles in the grounds of the stately home. This year organisers want to go bigger than ever before with a range of record-breaking challenges for participants among the 200 obstacles.
Rockers Ash and BBC Radio 6 Music DJ Craig Charles have been confirmed as headline acts for the after party.
Rat Race managing director Jim Mee said: “This year’s Dirty Weekend goes even bigger than previous years.
“It’s already the biggest obstacle course on earth but we thought we’d go a bit bigger. Our world record-breaking monkey bars will have a few extra rungs added; and our ‘Big One’ finale obstacle, which last year was as high as a house, will go one storey higher and have a bar fitted to the underside.
“We’ve also got our best ever line-up on the entertainment front, with Ash headlining our 5,000 capacity big top tent followed by a killer funk and soul DJ set from Craig Charles.”
The Dirty Weekend is now in its third year, having started at Burghley in 2013. Last year more than 6,000 people from across the country braved both the assault course and driving rains.
Competitors, many in fancy dress, battled up to 200 obstacles, including energy-sapping inflatables, mud runs, vertical walls and the infamous ‘Water Wipe Out’ zone.
Waves of runners set off from 8am on either a 13-mile for 20-mile courses.
The race was won by Jonathan Albon in a time of 2h34m12s.
Sheffield’s Reverend and the Makers and BBC Radio 1 DJ Greg James provided the entertainment for the shattered participants later in the evening.
Entry prices, which include the after party, begin at £139 for a solo runner, dropping to £119 per person for a team of 10.
One of those already signed up is Market Overton Cricket Club player Brian Makwana. Brian and a team of friends are running in aid of CDH UK, a charity that supports children with congenital diaphragmatic hernia. Brian’s son Wyatt was born with the condition and spent several months in hospital.
For more details on the event and to sign up visit www.ratracedirtyweekend.com.