Knowth burial mound in Newgrange, Boyne Valley, Ireland for St Patrick's Day

The Emerald Isle. It’s a good day to be green

For St Patrick's Day, we're featuring an image of the Knowth passage grave, part of the Boyne Valley tombs, a prehistoric landscape which has many tales to tell us of Ireland’s ancient past. This Unesco World Heritage Site is also home to the Newgrange and Dowth passage graves, henges and standing stones, as well as having Europe's largest concentration of megalithic art. Knowth, the largest in the complex, is a 40ft mound, 220ft wide with two passages beneath it which lead to separate burial chambers.

The structures predate St Patrick by nearly 4,000 years, and their original purpose is unclear. But on this day dedicated to all things Irish, they show off the engineering capabilities of the area's ancient population as well as the natural green beauty of the Irish countryside.