More than 3,000 free events are happening tonight as part of the 10th annual Culture Night.
1,500 venues are hosting free-of-charge events in towns and cities around the country.
People are advised to visit the website CultureNight.ie, for details of events in their local area.
Culture Night Co-ordinator Aimée van Wylick said lots of outdoor and pop-up events taking place, including a Galway City music trail, live 3D projections on the College of Commerce in Cork, bike tours of Dublin and a host of arts and crafts and historical events everywhere.
Dublin City Arts Officer Ray Yeates, said this event invites people to get involved in the capital's bid to become the city of culture in 2020.