The Hill of Tara was important from the Stone Age, when the Mound of the Hostages passage tomb was built about 5,000 years ago, but it rose to supreme prominence in the Iron Age and early Christian period as the seat of the high kings of Ireland. The palaces and halls are long gone and only earthworks remain: the great enclosure of Ráith na Rí, around 1,000 metres in circumference, the twin rings of Cormac's House and the Royal Seat, the long "Banqueting Hall", and the Lia Fáil, the coronation stone.
Don't expect buildings. What you get is a low, open hill with wide views over the Meath plain and a strong sense of how much history happened on it. The site is open all year and free to walk; the visitor centre in a former church charges for an audio-visual show, but guided tours were suspended for the 2026 season. Wear shoes for wet grass. It lies off the N3 about 12 kilometres south of Navan, east of Trim.