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.
During the Iron Age, a Celtic language and culture emerged in Ireland.
How and when the island of Ireland became Celtic has been debated for close to a century, with the migrations of the Celts being one of the more enduring themes of archaeological and linguistic studies.
However, summers are cooler than those in Continental Europe. The earliest evidence of human presence in Ireland is dated at 10,500 BC. The island was Christianised from the 5th century onward.
In 2011, the population of Ireland was about 6.4 million, ranking it the second-most populous island in Europe after Great Britain.
Just under 4.6 million live in the Republic of Ireland and just over 1.8 million live in Northern Ireland.
For other uses, see Ireland (disambiguation).) is an island in the North Atlantic.
It is separated from Great Britain to its east by the North Channel, the Irish Sea, and St George's Channel.
The fields were farmed for several centuries between 3500 BC and 3000 BC. The Bronze Age – defined by the use of metal – 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. Koch and others, Ireland in the Late Bronze Age was part of a maritime trading-network culture called the Atlantic Bronze Age that also included Britain, western France and Iberia, and that this is where Celtic languages developed.