GRANDSTAND tickets have almost sold out for the Australian International Three-Day Event that will run from this Friday to Sunday in central Adelaide.

As Australia's only four-star level event, it has attracted a record number of competitors.

Olympic gold medallists Wendy Schaeffer and Stuart Tinney will battle it out against some of the biggest names in the equestrian world, including Beijing silver medallists Shane Rose, Megan Jones and Sonja Johnson, and the defending champion in the Olympic-level four star class, Christopher Burton.

Almost 110 riders have entered the event, up from 80 last year.

Up to 30,000 people are expected to flock to Rymill Park to see some of horse riding's biggest stars in action.

"It's terrific to see the people of South Australia getting behind us and supporting us in this way and if you don't yet have a ticket, don't panic" said event director Gillian Rolton.

"There are still some available in the grandstand, while terrific vantage points are available in the general areas as well."

"Not only will spectators have the chance to see world-class riding, but they can also enjoy a full program of fun events including a fantastic luncheon, fashion parades, a Masterclass with Olympic judge Martin Plewa and a flamboyant Dressage to Music display by Spaniard Blas Lago on Northern Hector on dressage day, the Grape and Gourmet Gallop featuring the best of South Australia's food and wine, and an expanded trade and lifestyle village."

The event will also play host to New Zealand's finest horse and rider combinations competing against the Aussies for the hotly contested Trans Tasman Challenge.

The Kiwis won in New Zealand in 2007, so the Australians will be out to snatch the title back.

With the Saturday of the event coinciding with the running of the much-loved Christmas Pageant, organisers are theming the day as a "family day", encouraging families to enjoy the fabulous sights and sounds of the Pageant and then spend the afternoon relaxing in the parklands.

For the kids, there'll be plenty to see and do in the Kiddies' Choral, including pony rides, a dedicated playground area, bouncy castle and face painting. Spectacular showjumping, a challenging cross-country course and tests of elegance and precision in the dressage arena are features of the Adelaide event, one of only six four-star events in the world.