The Island – Land episode 1: The story of the island of Ireland’s epic geological journey, spanning 1.8 billion years. In this first episode, we reveal how two ancient continents swallowed an ocean as they slowly approached each other over millions of years. The collision point would eventually become Ireland, and we show how the battle scar from this immense fusion runs like a suture in the rock from the Shannon Estuary in County Limerick to Clogherhead in County Louth.
This merging and folding of lands took millions of years, and, even after this ancient coming together, the island’s story had only just begun. As the rocks continued to move very slowly north, we explore how changing sea levels submerged Ireland in shallow tropical waters, creating the limestone deposits that dominate our landscape and are exposed so impressively at The Burren in County Clare.
We examine evidence for Ireland’s long-lost deserts that formed as the island crossed the equator past present-day Egypt. In Newfoundland, the rocks reveal the legacy of the colossal forces that slowly ripped Ireland from North America over millions of years, and, on the Antrim coast, we investigate the volcanic hotspots that created the iconic Giant’s Causeway around 60 million years ago.
The Island – Land episode 1
During the last glacial period, and until about 16,000 BC, much of Ireland was periodically covered in ice. The relative sea level was less than 50m lower resulting in an ice bridge (but not a land bridge) forming between Ireland and Great Britain. By 14,000 BC this ice bridge existed only between Northern Ireland and Scotland and by 12,000 BC Ireland was completely separated from Great Britain. Later, around 6100 BC, Great Britain became separated from continental Europe. Until recently, the earliest evidence of human activity in Ireland was dated at 12,500 years ago, demonstrated by a butchered bear bone found in a cave in County Clare. Since 2021, the earliest evidence of human activity in Ireland is dated to 33,000 years ago. By about 8000 BC, more sustained occupation of the island has been shown, with evidence for Mesolithic communities around the island.
Some time before 4000 BC, Neolithic settlers introduced cereal cultivars, domesticated animals such as cattle and sheep, built large timber buildings, and stone monuments. The earliest evidence for farming in Ireland or Great Britain is from Ferriter’s Cove, County Kerry, where a flint knife, cattle bones and a sheep’s tooth were carbon-dated to c. 4350 BC. Field systems were developed in different parts of Ireland, including at the Céide Fields, that has been preserved beneath a blanket of peat in present-day Tyrawley. An extensive field system, arguably the oldest in the world, consisted of small divisions separated by dry-stone walls. The fields were farmed for several centuries between 3500 BC and 3000 BC. Wheat and barley were the principal crops.
The Bronze Age began around 2500 BC, with technology changing people’s everyday lives during this period through innovations such as the wheel; harnessing oxen; weaving textiles; brewing alcohol; and skilful metalworking, which produced new weapons and tools, along with fine gold decoration and jewellery, such as brooches and torcs.
