Riders set out on the Mongol Derby.
South African architect Charles van Wyk, 28, was declared joint winner of the Mongol Derby along with Mongolian rider Shiravsambo Galbadrakh, the pair reaching the finish line in Dadal on August 29.
The race, which began at Kharkorin, took just over seven days for the first riders to complete. The competitors raced between 23 horse stations placed 20-40km apart, where they were required to change mounts.
The event generated controversy after the founder of The Long Riders' Guild, CuChullaine O'Reilly, voiced fears over the safety of the 26 riders in the event and the welfare of the 700 native Mongolian horses to be used in the relay.
He labelled the event an ill-advised equestrian misadventure.
The organisers, a British firm called The Adventurists, responded with more information about the event, including the use of satellite tracking devices and details about the veterinary care to be provided to the horses.
The Adventurists said two riders suffered concussion and one of them also sustained back injuries after falling off their horses in the first stages of the race. They were forced to withdraw.
Champion jockey Richard Dunwoody rode the first two legs of the race before returning to Britain because of prior commitments.
A further rider received medical attention after a fall but was deemed fit and healthy to continue.
The remaining 23 riders finished the race, the last three crossing the finish line together on September 2.
Organisers said the arrival ceremony and celebrations were brought forward after the riders finished the race faster than expected.
Jenny Weston, an International Equestrian Federation (FEI)-accredited four-star endurance vet, was among the vets flown to Mongolia to oversee horse welfare and provide veterinary care.
She said there were no equine emergencies during the race.
"From a veterinary perspective there was not much to do for the horses involved in the Mongol Derby apart from assess their suitability before the riders arrived ... then checking that the horses that had been ridden in were recovering well (mainly based on heart-rate recovery and gut sounds).
A horse is vet checked after a leg.
"A couple of horses were involved in freak accidents (that's just what horses do) but ultimately less than 2 per cent of the horses required any treatment and that was all minor first aid.
"Horse riding is essentially a dangerous sport and throwing semi-wild mounts and an exceedingly remote location into the mix meant that the dangers to the riders were real.
"Along with horse welfare, sensible behaviour by the participants was paramount to ensure that no major problems were encountered."
Weston said organising the event was a huge undertaking and would not have been possible without the support of the local Ministry of Agriculture, veterinarians, herders and horse trainers.
Race winner Van Wyk said the hospitality of the Mongolian people was amazing.
"We have been brought into their homes and looked after like members of their family; it felt like being at home. Overall, it has been a great experience to live in the steppe and ride Mongolian horses."
British rider Holly Budge, 30, welcomed the adventure. "Some of the horses were pretty wild and feisty ... but they were really fun to ride.
"At the finish line, if you'd have said 'off you go, ride back 1000km' I would have done it, definitely! And it wasn't just me - there were a few people that said that."
Annelie Simmons, 27, from London, said she was amazed by the strength and tenacity of the Mongolian horses. "They were tough, hardy and strong. There was never a single point whereby I felt we were asking too much of them, if anything we could have ridden harder and faster but I treated each horse as if it was my own - with care and respect."