Archaeologists tell us that the first settlers did not arrive in Ireland until around 8000 BC during the period known as the Mesolithic age. This comparatively late event in pre-history is probably due to the last Ice Age. One of the most famous sites from this era is Mount Sandel near Coleraine just outside the modern Limavady Borough. The standing stones and small stone circles that dot the Limavady area landscape are remnants of the Neolithic period from about 4000 BC. Limavady town itself and many of the surrounding villages have Celtic roots. No one knows for sure just how old the original settlement of Limavady is. The Celts first arrived in Ireland about 350 BC and settlements in the Banagher area of the Limavady Borough date from before the 5th century AD.