Ireland's hot, arid climate of 400 million years ago brought with it extreme weather events which would leave an indelible mark on the landscape.

The Caledonian mountain range which was created when the two landmasses were fused together, began to erode very quickly.

The main drivers of this erosion were flash floodsng, a natural phenomenon common in this kind of climate.

Dried up river beds would suddenly fill with rainwater, swell and become raging torrents.

This is a particularly dangerous form of flooding as it combines the destructive power of a flood with incredible velocity and unpredictability.

It has the power to move boulders, tear out trees, and, in today's world, to destroy buildings, and demolish bridges.

Walls of water can reach heights of 3 to 6 metres and generally carry a huge amount of debris with them, and they can occur within a few minutes of heavy rainfall.

During the erosion of the Caledonian Mountains, vast quantities of rocks and sediment were loosened and then carried by the torrential rivers before being dumped at the foot of the mountains where they formed deposits.

The result is often referred to as Old Red Sandstone rock.

And that is what is visible here on these caves at Cushendun.

The remains of a vast mountain range, weathered and eroded by wind and water, ready for use in the modern day construction industry.