Here are some of the horses and riders to look out for over the next few days.
Endurance (26-27 September)
Reigning WEG champions: France (team) and Miguel Vila Ubach/Hungares, ESP (Individual)
Maria Alvarez Ponton. © Gilly Wheeler
The consistent performances of the French sees them hotly tipped for the team honours, but the UAE will be giving it their best shot to retain the World title they claimed in 2008. Endurance tests the speed and stamina of the horse and the skill of the rider who must temper the pace in order to complete the course in good condition. The competition is run over a distance of 160km, with regular veterinary stops to check the horse's fitness to continue. The competitor who finishes in the quickest time is the winner, but there is still a final veterinary inspection to get through.
The sport of Endurance has grown rapidly since the 2006 World Equestrian Games and is now the FEI's fastest growing discipline.
Reining (25-30 September)
Reigning WEG champions: USA (Team) and Duane Latimer/Hang Ten Surprize/CAN (Individual)
Rudi Kronsteiner. © NRHA/Waltenberry
The USA are strong favourites for team gold having won in Aachen in 2006, but Canada so narrowly missed out that day - losing by just 0.5 points - and are likely to return with something to prove. South American reiners have been working long and hard to step up their game along with many of the other well known reining nations, including Germany, Italy and Australia.
In the Individual Championship, Rudi Kronsteiner (AUT) will be looking to put in a great performance with his consistent partner Einstein's Revolution, but there will be plenty of strong opposition. This year really is an open playing field, and it will take steady nerve and strong horse power to reach the top of the podium.
Laura Bechtolsheimer © Horsesports Photographic
The burning question will be whether the mighty Dressage nation of Germany can regain supremacy from the Netherlands, current European Champions, but yet to win a World team title. The supreme artist Isabell Werth is back in action, following the birth of her child last year, but the Dutch, in the form of Edward Gal and the record-breaking stallion Totilas and Adelinde Cornellissen on the breathtaking Parcival, now have the bit between their teeth and may be hard to beat.
The host nation, too, is expected to produce a competitive showing, especially from the 2009 World Cup winners Stefan Peters and Ravel, while Laura Bechtolsheimer and Mistral Hojris have been making waves for Great Britain.
Ingrid Klimke and Butts Abraxxas. © Kit Houghton/FEI
Eventing is a familiar sport at Kentucky, home of the world-famous Rolex CCI4*, but the vross-vountry course, across the Horse Park's magnificent rolling acres, will have been given a totally new look by Course Designer Mike Etherington-Smith.
Once again, Germany looks the nation to beat, with three members of the winning team from Aachen 2006 returning to the fray - Ingrid Klimke, Andreas Dibowski and Frank Ostholt.
Other former gold medalists in the field include Mark Todd and Andrew Nicholson, members of the winning New Zealand squads in Stockholm 1990 and Rome 1998; Mary King (GBR) and Kristina Cook (GBR), members of the winning British team in The Hague (NED) in 1994; and Jean Teulere, France's Individual World Champion at Jerez (ESP) in 2002.
Jumping (4-9 October)
Reigning WEG champions: Netherlands (team) and Jos Lansink/Cumano/BEL (Individual)
McLain Ward and Sapphire
The USA will also challenge strongly for the individual honours, with McLain Ward and Sapphire in sparkling form in recent months. Frenchman Kevin Staut is currently leading the Rolex World Rankings and other major contenders include 2010 Rolex FEI World Cup champion Marcus Ehning from Germany and Olympic champion, Canada's Eric Lamaze. But the individual title is a wide-open affair. Riders must have a really talented horse to make it to the closing stages when it all comes down to horsemanship as the top four go head-to-head in the deciding competition during which they exchange mounts. Experience, and the ability to adapt to a horse you have never ridden, are key to victory.
Great Britain has won team gold in every championship since the sport began, and fields the most medalled rider in history, Lee Pearson, plus Anne Dunham, the only rider to have competed at every Paralympics.
Para-Dressage, which joined the FEI disciplines in 2006, provides riders with physical disabilities the opportunity to compete in high performance equestrian sport alongside able-bodied riders from all over the world.
The FEI was one of the first international governing bodies to regulate sport for both able-bodied and disabled athletes.
Vaulting (6-10 October)
Reigning WEG champions: Germany (team) and Megan Benjamin, USA (Female Individual), Kai Vorberg, GER (Male Individual).
In this demanding sport, judged over two rounds consisting of compulsory and freestyle tests, competitors must show technique, balance and athleticism along with creativity.
The performance of the horse has become much more important since the last World Equestrian Games in Aachen, as this vital member of the vaulting team must remain calm, controlled, balanced and happy while being lunged by a longeur who ensures a steady, true canter is maintained on a circle as the vaulter executes their movements. The horse's way of going now accounts for 20% of the overall score.
The Austrian team won the 2009 European Championships at Bokeberg in Sweden, where Joanne Eccles claimed the Individual Female title and the British rider goes to Kentucky as one of the favourites.
Germany's Kai Vorberg, defending Male Vaulting Champion at the Alltech FEI World Equestrian Games, was silver medallist at last year's European fixture where Nicolas Andreani from France took gold.
Carriage Driving (7-10 October)
Reigning WEG champions: Germany (team) and Felix Marie Brasseur, BEL (Individual)
Driving is a growing sport in the USA and the goal of World Championship Course Designer Richard Nicoll is to stir the enthusiasm of the large number of spectators at Kentucky Horse Park during the forthcoming Games.
Dutch, German, Swedish, Swiss and American sides will battle it out for the team medals, and will be joined by Australia's Boyd Exell, twice winner of the Rolex FEI World Cup Driving Final, who will be bidding for the individual title.
There are three phases of competition - Dressage, Marathon and Obstacle Cones - similar to Eventing, but with four horses.