Near Abbasanta lies the archaeological site of Santa Cristina, world-famous for its sacred groundwater well built over 2,500 years ago. Constructed with finely dressed basalt blocks fitted together with precision, the structure showcases advanced astronomical knowledge from the Nuragic era. During the equinoxes, sunlight penetrates straight through the top opening to illuminate the water below. The trapezoidal stone staircase leading down to the well creates a optical illusion of symmetry, appearing like a modern engineering work rather than an ancient shrine.