Lighting on many of Dublin’s landmarks will be switched off this evening as the capital joins dozens of cities across the globe to mark Earth Hour.
The Customs House, Four Courts, Aras an Uachtarain, the courtyard in Government buildings and Leinster House will all switch off the lights between 8pm and 9pm as part of the international effort to raise awareness about climate change.
Diners at the Four Seasons restaurant will be tucking into their food by candlelight for the entire evening as the global hotel chain has signed up to take part.
Green Party Leader and Minister for the Environment John Gormley urged the public to take part.
"Earth Hour is a wonderful opportunity for people and businesses to switch off and switch on to a new way of thinking," Minister Gormley said.
"Through participating in Earth Hour, people can show their commitment to taking action on climate change."
Galway and Limerick City Councils as well as 15 town and county councils around the country have also pledged support for the initiative.
Astronomy Ireland will be setting up high-powered telescopes to allow people to take advantage of the night sky, normally swamped by bright city lights.
The first Earth Hour took place in Sydney last year with more than two million people taking part, before spreading to become an international event for 2008.
Up to 30 million people were expected to switch off their lights for 60 minutes by the time "Earth Hour" - which started at 8 p.m. in Suva in Fiji and Christchurch in New Zealand - completed its cycle westwards.
More than 380 towns and cities and 3,500 businesses in 35 countries signed up for the campaign.
Lights at Sydney's Opera House and Harbour Bridge were switched off and Australians held candle-lit beach parties. In Bangkok, some of the city's business districts, shopping malls and billboards went dark, although street lights stayed on.
In Copenhagen, the famed Tivoli Gardens said it would also switch off along with the City Hall.
In Britain several historic buildings including Prince Charles' private residence Highgrove House, London City Hall, Winchester Cathedral and even the Government Communication Headquarters radio monitoring station pledged to switch of.
Other cities involved in this year's global campaign include Chicago, Manila, Dubai and San Francisco. It is designed to highlight the wastefulness of non-essential lighting.