A 3-year-old girl has been airlifted to hospital after an accident at Kielder Reservoir.
The girl injured her leg on a slide.
She was treated at scene by a paramedic and a doctor and then flown to the Cumberland infirmary in Carlisle.
Her injuries are not thought to be life-threatening.
The training ends and the event begins, it is marathon day at Kielder for the 1,500 runners taking part. The distance is 26 miles and 385 yards. Event organisers estimate the best athletes will complete the race in less than two and a half hours. The finish line is at Leaplish Waterside Park.
Runners are flocking to Kielder ready for the marathon. The Kielder 10K and Kielder Run-Bike-Run events both begin at 1pm on October 6. There are almost 550 people taking part in the 10K, twice as many as last year. For the first time, the event is full.
The Run-Bike-Run is a relay event where 40 teams of three tackle the marathon distance split into three parts: an 11km run, a 26km bike ride and a 5km run.