The Burren, County Clare, Ireland

In Western Ireland lies a barren, but beautiful landscape of windswept craggy limestone known as the Burren. The word Burren (aproximate pronounciation baihrn) descends from the Gaelic word bhoireann variously translated as 'stony place' or 'great rock'.

The Geology:
During the ice age (Pleistocene) the massive continental glaciers that moved across northern Europe stripped most of the soil from this corner of Ireland. Carbonic acid- the result of rainwater mixed with carbon dioxide, slowly began to widen cracks in the rock, creating the craggy furrowed landscape.

The Burren is an example of karst- a landscape dominated by soluable rocks, most often limestone. Where there is karst there is typically caves, and the Burren is no exception. The hills of the region are riddled with caves, several of them containing underground streams (there is water in the Burren, just not at the surface). One of these caves, Pol an Ionain, contains the largest stalactite in Europe, also one of the longest free-hanging stalactites in the world.

The limestone itself was deposited during the Carboniferous period, when Ireland was covered in a warm shallow sea. Fossils of corals and other sea life are a testament to the origin of the rock.

The Botany:
The Burren is world renowned for its wildflowers. What soil there is has collected in the cracks and furrows widened by dissolving away the limestone. The soil, not abundant enough for trees or shrubs, is able to support wildflowers in abundance. What is truly remarkable though, is the diversity of species. Flowers typical of Mediterranean to Arctic environments are found together, in part nurtured by western Ireland's mild climate which is due to the moderating effect of the Gulf Stream.

The landscape itself offers a clue to how all this diversity can be supported. The bare rock heats up faster in the sun, supporting the warm loving Mediterranean species growing in the cracks, but the deeper shaded cracks support the cool loving arctic species.

The History:
One of the best preserved bronze age archeological sites in Ireland is in the Burren. Poulnabrone is a megalithic structure built on top of a crag in the limestone, which was used as a burial chamber.

When Oliver Cromwell's scouts returned from the Burren they reported that it had "neither water enough to drown a man, nor tree to hang him, nor soil enough to bury him."

Some suggest that there may have been some soil cover in the historical past, but as settlers began to cut down the trees the thin fragile soils simply eroded away.

See also:

Geology of the Burren