Newgrange is a passage tomb in the Republic of Ireland dating from around 3,300 to 2,900 BCEogan 1991 For a few days around the Winter Solstice light shines along the central passageway into the heart of the tomb. What makes this notable is not that light shines in the passageway, but that it does not do so through the main entrance. Instead it enters via a hollow box above the main doorway discovered by Michael O'Kelly.O'Kelly 1982:123–24 It is this roofbox which strongly indicates that the tomb was built with an astronomical aspect in mind. In their discussion of the credibility of archaeoastronomical sites, Cotte and Ruggles gave Newgrange as an example of a Generally accepted site, the highest of their four levels of credibility. Clive Ruggles notes:
