Loughcrew
Loughcrew (Irish: Loch Craobh) is near Oldcastle, County Meath, Ireland. (Sometimes written Lough Crew). Loughcrew is a site of considerable historical importance in Ireland. It is the site of megalithic burial grounds dating back to approximately 3500 and 3300 BC, situated near the summit of Sliabh na Caillí and on surrounding hills and valleys. Passage tombs on the site are aligned with the Equinox sunrise.
Loughcrew is one of the four main passage tomb sites in Ireland (the others are Brú na Bóinne, Carrowkeel and Carrowmore). No comprehensive dating programme has been conducted there, but the monuments are estimated to date from about 3300 BC. The sites consist of cruciform chambers covered in most instances by a mound. A unique style of megalithic petroglyphs are seen there, including lozenge shapes, leaf shapes, as well as circles, some surrounded by radiating lines.
The site is spread across three hilltops, Carnbane East, Carnbane West, and Patrickstown. The Irish name for the site is Sliabh na Caillí, which means "mountain of the hag". Legend has it that the monuments were created when a giant hag, striding across the land, dropped her cargo of large stones from her apron. The orthostats and structural stones of the monuments tend to be from local green gritstone, which was soft enough to carve, but which is also vulnerable to vandalism.
In 1980 Irish-American researcher Martin Brennan discovered that Cairn T in Carnbane East is directed to receive the beams of the rising sun on the spring and autumnal equinox - the light shining down the passage and illuminating the art on the backstone. Brennan also discovered alignments in Cairn L (53°44′36″N 7°08′03″W / 53.743299°N 7.134040°W), Knowth, and Dowth in the Boyne Valley. The Cairn T alignment is similar to the well-known illumination at the passage tomb at Brú na Bóinne (Newgrange), which is aligned to catch the rays of the winter solstice sunrise.
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