Up to 100,000 people are expected to attend the Dublin Horse Show, which is taking place in the RDS this week.

The five-day event, which begins on Wednesday, is expected to bring in some €45 million to the local economy.

"The show nets almost half of the annual €97 million generated by the horse trade in Ireland, with more than 1,500 horses on display throughout the week," Minister for Transport, Tourism and Sport Michael Ring said.

Mr Ring also said “adventure sport” was one of the best sports for attracting tourists, including the “best spenders”.

There will be a prize fund of almost €1 million for professional riders.

"Throughout the decades the Horse Show has always been one of the social events of the summer, but it has always been a substantial sporting event too, which in 2015 is reflected in the prize fund," RDS chief executive Michael Duffy said.

“It’s the signature event for the RDS. It is one of the events of the summer that has a huge tradition behind it and the society is very committed to it and very anxious to develop it.”

He said the Aga Khan competition would take place on Friday, the Land Rover Puissance on Saturday, and the Longines International Grand Prix on Sunday.

The contest for the Aga Khan Trophy is one of the highlights of the week and Ireland will be one of eight countries to compete. Alongside a five-day equestrian programme the event, in its 142nd year, will also feature 300 stands showcasing leather goods, crafts and equine products.

Started in the 19th century, the Horse Show was originally founded to encourage and promote the Irish horse industry, as one part of the RDS philanthropic aims.

The RDS is planning to spend €35 million redeveloping the main stadium at its grounds in Ballsbridge.

It is understood a Government grant covering up to half of the cost could be sought.

The balance would come from the RDS’s own resources and from naming rights to the stadium, which could be worth up to €10 million for 10 years.