Aengus's home in myth, the Brug na Boinne, is not merely a poetic setting but one of the most carefully studied prehistoric monuments in Europe, and the identification of the two has given the god an unusually concrete archaeological anchor. Newgrange, the great passage tomb the name refers to, was built around 3200 BCE, centuries before the pyramids of Giza, and consists of a vast mound covering a long stone passage leading to a corbelled chamber. Its most celebrated feature was confirmed only in 1967, when the archaeologist Michael J. O'Kelly established that a specially built opening above the entrance, the roof-box, admits a narrow beam of sunlight along the passage to the chamber only around the winter solstice, a piece of Neolithic engineering precise enough to still work exactly as designed after five thousand years. Whether the builders who raised Newgrange had any concept resembling the god later called Aengus is unknowable, since the monument predates the Irish mythological texts by well over three thousand years, and the association is a medieval literary layer placed onto a much older structure.
The site's importance was recognised formally when Newgrange and the wider Brú na Bóinne complex, including the neighbouring tombs of Knowth and Dowth, were inscribed as a UNESCO World Heritage Site in 1993, and the solstice alignment now draws large public interest, with a lottery held each year for a small number of places inside the chamber at dawn on the solstice. Aengus's myth of winning the mound by a clever trick of words gave a much later, literate culture its own explanation for who owned this astonishing structure, built centuries after the stones themselves were raised.