Fourknocks Passage Grave - Tuama Pasáiste na bhFuarchnoc

Fourknocks Passage Tomb (Irish: Tuama Pasáiste na bhFuarchnoc) is located 2.7 km (1.7 mi) northwest of the village of Naul (Irish: An Aill) close to a hilltop overlooking the Delvin River, County Meath (north part of Fingal), Ireland  (Irish: An Ailbhine, Contae na Mí, Éire). The tomb dates to 3000–2500 BC and has a short passage leading into a wide round chamber with three smaller offset chambers. When investigated it was found that the original roof was possibly a wooden structure or animal skin supported by a central pole. After excavation a concrete roof was placed over the chamber for protection.

It was first excavated in 1950-52 when cists, grave goods including a foot bowl and a carved antler pin, urns containing cremated remains were found. The passage in the tomb is about 5 m (17 ft) leading into the chamber that is 5.5 m (18 ft) by 6.4 m (21 ft) with three recesses. There are twelve carved stones inside and two of the lintels have a chevron decoration. Fourknocks Passage Tomb is a National Monument. 

Image: Carved stone at Fourknocks - Fourknocks-Ritzverzierungen author Wandervogel

Links: Discover Boyne Valley and also Knowth.com.