Sixty million years ago Antrim was subject to intense volcanic activity, when highly fluid molten rock was forced up through fissures in the chalk bed to form an extensive lava plateau.

The dramatic cliff like edge of the plateau forms the Causeway coastline. The larger fissures, through which the lava flowed, can be clearly seen as bands of dark rock which cut down the cliff faces and jut out to sea. There were three periods of volcanic activity which resulted in the flows, known as the Lower, Middle and Upper Basalts.

It is the Middle Basalts rocks which forms the columns of the Giants Causeway. The rapidly cooling lava contracted and variations in the cooling rate resulted in the world famous columnar structure.

The columns are mainly hexagonal though there are some with up to eight sides. Weathering of the top of of the lower Basalts formed the Inter Basaltic Bed - the band of reddish rock which is a feature of the area.

Ireland is situated in the Atlantic Ocean and separated from Great Britain by the Irish Sea. Half the size of Arkansas, it occupies the entire island except for the six counties that make up Northern Ireland. Ireland resembles a basin—a central plain rimmed with mountains, except in the Dublin region. The mountains are low, with the highest peak, Carrantuohill in County Kerry, rising to 3,415 ft (1,041 m). The principal river is the Shannon, which begins in the north-central area, flows south and southwest for about 240 mi (386 km), and empties into the Atlantic. 

Here are some more pictures of Ireland. Learn some Irish Gaelic at the bottom. Ive got a slide show of Irish doors, do not ask me why. Do not try and rush the satellite map. When you look at the weather in Ireland, switch to full graphics version.