Tens of thousands of people will converge on Kildare over the next three days for the 2010 National and European Ploughing Championships.
It estimated the championships will generate more than €10m for the local economy.
The Ploughing Championships are returning to Cardenton outside Athy for the second year running. Cardenton also hosted the first event in 1931.
President Mary McAleese will officially open the championships at 12 noon, but the action around the 700-acre site will get underway from 9am.
Hundreds of competitors will battle it out for ploughing titles, but there is plenty of activity off the field too, with more than 1,100 exhibitors.
It is estimated 25,000 steaks, 20 tonnes of burgers, sausages and bacon, 10,000 eggs, 12,000 litres of milk and 6,000 litres of ketchup will be consumed over the three days.
People travelling to the event are advised to allow plenty of time and to adhere to the special Garda traffic plan in operation.