More than 150,000 spectators are expected to attend the National Ploughing Championships, which got under way at Grangeford near Tullow, Co Carlow, at 10.30am this morning.
The national competitions are taking place today and tomorrow.
The World Ploughing Contest, with more than 300 competitors from 27 countries, is being held on Friday and Saturday.
Gardaí have a special traffic plan in operation in the area.
This year's rural festival marks the 75th anniversary of the National Ploughing Association.
Irrespective of weather conditions, about 50,000 people a day usually attend these championships.
The President Mary McAleese, Taoiseach Bertie Ahern and several Government ministers are expected to join the huge crowds at the 700-acre site over the next four days.
Apart from the competitions, there are 800 exhibition stands - with special focus this year on healthy living, farm safety, and renewable energy.
The weekend attraction is expected to be especially popular with the growing number of part-time farmers.
