Religious and Spiritual Significance: One prevailing theory is that Newgrange had religious and spiritual significance. Its alignment with the rising sun during the winter solstice, when sunlight penetrates the inner chamber through a roof box, suggests a connection to sun worship. This alignment may have symbolized the renewal of life, the victory of light over darkness, and the cyclical nature of the seasons, all of which are common themes in ancient religions.
Calendar and Agricultural Use: The precise alignment of Newgrange with the solstices suggests that it could have functioned as a primitive calendar. The changing position of the sun's rays inside the tomb may have helped early agricultural societies mark important dates for planting or harvesting crops, thereby assisting in agricultural planning and the organization of their agricultural calendar.