Survival skills will be important to deal with the conditions and there is a 5kg luggage limit. Mr Wilks will take a set of clothes, camera, sleeping bag, an extra jacket, map and compass, duct tape and a heavy duty needle to fix any broken gear. Competitors either stay with Mongolian herders or camp, tackling unfamiliar terrain and eating food such as fermented horse milk and goat stews.
"It'll be the hardest thing mentally and physically I've ever done and I'm interested to see how it goes," he said. "Crossing the finish line in one piece is probably the prize."
Mr Wilks will move home from Thames in April to begin his three months of full-time training, riding as much as he can and practising navigating with a map and compass through the Kaimai Range. He needs to raise a minimum of 1000 ($2060) for the event's official charity, Cool Earth, and his chosen charity, Kiwi Care Team.
Mr Wilks also needs to raise the 7995 entry fee to cover the 25 to 27 race horses, three training horses, vets and medics for the rider and horses, the 25 stations and a tracking device. The race begins on August 5.
The Mongol Derby
* The 1000km course recreates Chinggis Khaan's legendary empire-busting postal system, with riders changing horse every 40km, and living with herders or camping under the stars.
* The 2015 Derby will run from August 5 to 16, with pre-race training from August 2 to 5.
* Help Ben get to Mongolia: Follow the "Adventures of Ben Wilks" on Facebook.