Newgrange
Newgrange is one of the most extraordinary prehistoric monuments in the world, a passage tomb built approximately 5,200 years ago in County Meath that predates both Stonehenge and the Egyptian pyramids by several centuries. The site is located in the rich agricultural valley of the River Boyne, an area so densely packed with Neolithic monuments that it has been recognised as one of the world's great prehistoric landscapes and designated a UNESCO World Heritage Site under the name Brú na Bóinne, the Bend of the Boyne. The monument consists of a large circular mound approximately 80 metres across and 13 metres high, built with an estimated 200,000 tonnes of stone and earth. Within the mound a 19-metre stone-lined passage leads to a cruciform central chamber whose corbelled stone roof has remained waterproof for over five millennia, a testament to the extraordinary engineering skill of the Neolithic builders. The passage and chamber were constructed in precise alignment with the rising sun at the winter solstice, so that on and around the shortest day of the year sunlight enters through a specially constructed roof-box above the passage entrance and travels along its entire length to illuminate the chamber floor in a shaft of gold. The fact that this alignment was deliberately engineered five thousand years ago, at a time when human civilisation in Ireland had no writing, no metal tools and no wheeled vehicles, is genuinely astonishing. The precision required to align the passage across a distance of nearly twenty metres to within a fraction of a degree represents a level of astronomical observation and architectural planning that challenges comfortable assumptions about the capabilities of prehistoric societies. The exterior of the monument is also visually striking. The facade facing the southeast is reconstructed in brilliant white quartz from the Wicklow Mountains, the stones interspersed with large dark granite boulders from County Louth. The effect is dramatic and somewhat controversial among archaeologists, since the reconstruction represents an interpretation rather than a certainty. The kerb of large kerbstones surrounding the base of the mound includes several decorated with the abstract spiral and geometric patterns that characterise Neolithic art at Brú na Bóinne, including the famous triple spiral stone at the entrance. Visits are by guided tour only, departing from the Brú na Bóinne Visitor Centre across the river, and booking in advance is strongly recommended. The annual winter solstice illumination is allocated by lottery and is applied for by thousands of people from around the world.