Cliffs of Moher History

The cliffs have a long rich history, dating back millions of years to the forming of the Cliffs of Moher. The cliffs get their name from a ruined fort Mothar, this fort was damaged during the Napoleonic wars period in the 1800s. The old meaning in Irish for Mothar is the ruin of a fort.

The area covers a fairly long distance of 8 kilometres. It is believed that the Cliffs of Moher were formed about 320 million years back, this was during the upper carboniferous period. Large amounts of rainfall caused floods that washed mud and sand into flowing rivers out to the sea. This area was much hotter back then.

The silt and mud were collected into piles, over the years, the sections became compressed into hard rock, which over time formed the wonderful structure we have today. 

See our Cliffs Of Moher Facts page for interesting info about the cliffs.

The rock face is made of different types of rock, sandstone, shale and flagstone all appear on the face of the cliffs. Sections of the rocks layer of the cliffs vary from metres to centimetres in parts. Each section would have been impacted by a certain time period, which is effectively chapters of time periods. 

The whole area is taught to be a gemological laboratory that holds very interesting deposition in deep water sea sediments. The cliffs have been affected by erosion over the years, this is evident by the famous Branaunmore sea stack visible next to the cliffs.

This stack shows the level of erosion that has taken place over the millions of years since the forming of the cliffs. The area is littered with sea caves and sea stumps. The area has lots of fossils, and ripple marks are shown in some areas.

Hags head tower to the left-hand side was built in 1805 by the English army, the tower was used as part of a telegraph system, used to warn of invading French boats and ships. The tower is in a ruined condition today.