The Hill of Tara was the ancient seat of the High Kings of Ireland. There are a multitude of remains on the hill, including a passage mound, the Mound of the Hostages, which dates to between and other earthworks and structures.
Cave carvings inside the passage tomb at Loughcrew, Ireland. Older than stonehenge. Thought to be the tomb of Jeremiah the prophet. Carvings depicting the journey of Jeremiah across the ocean to Ireland.