It is small and well preserved and was carefully built over a spring that has been active for thousands of years and surrounded by a timeless landscape. In this scenario, you will find the sacred spring of Su Lumarzu, at the end of a path that unwinds from the very small medieval village of Rebeccu, on the edge of the Santa Lucia plain, in the Logudoro territory of Bonorva. The building consists of an atrium and a small cell, where the water that flows from the vein of spring water is collected. The rectangular atrium is paved and, inside it, you will notice bench-seats against the walls and a niche. The construction material used was basalt, with evenly-cut squared ashlars positioned in rows. Access to the cell is through a monolithic slab, onto which a trapezoid-shaped entrance opens up. The cell has a tholos roof, which ends with a horizontal slab on which a Latin cross was engraved - although it is not known with certainty when - and probably had the aim of ‘Christianising’ a place of pagan worship.