The mailing, created by Entire, features made-up artwork placing typical Badminton cross country features in Irish landscapes. For example, hurdles are placed in the formal gardens of Bantry Bay country house. The tagline is "Ireland: Land of the Horse".
Ian Bates, creative director of Entire, said: "The activity is designed to establish in the punter's mind that Ireland is the obvious place to go for horse-riding holidays."
As well as describing the appeal of the country as a place for horse riding, the mailing offers the chance to win a 拢2,000 riding holiday.
It also directs recipients to the Tourism Ireland website, where they can find out more information, and reminds them to pick up a free DVD from the Tourism Ireland stand at Badminton.
The tourist board is sponsoring this year's event, which allowed it to send the mailing to the 10,000 people who pre-booked their tickets for 2005 at last year's event.
Badminton runs for four days from today and will attract around 120,000 people. The headline sponsor is Mitsubishi Motors.
This year riders include Olympic gold medallists Matt Ryan from Australia and Britain's Leslie Law.
Tourism Ireland last year appointed Entire to handle all of its below-the-line communications for three years.
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