Known variously as Tobar Rahlan or Tobar Assicus, this sacred site has been attributed to three different saints over the years; St. Naal, St. Ciaran, and St. Assicus of Elphin, though the true dedication remains uncertain. Writing in 1936, Ó Muirgheasa noted that “a faithful few still perform the turus there”, referring to the traditional pattern of prayer and pilgrimage that continues at the site. Across the water in Malinbeg itself, the ruins of St. Ciaran’s chapel mark another point of devotion, where locals practised their religious observances until the late 19th century.

The well house itself is a remarkable piece of early medieval architecture, built in a distinctive trapezoidal shape with its narrow entrance facing north. Standing 1.3 metres high, its walls are constructed from carefully coursed stonework, with regular flat slabs forming the inner faces near the entrance, whilst the rear incorporates rounded beach boulders up to 40cm across. The structure measures 1.47 metres wide at its open northern end, broadening to 2.65 metres at the southern end where it merges with the boundary wall of the larger enclosure. The roof consists of flat schist slabs topped with a low mound of granite pebbles, and remarkably, a 75cm high cross slab bearing a simple Latin cross on both faces stands erect in the roof, held in place by a specially notched stone.

Archaeological investigations have revealed additional features that speak to the site’s long history of veneration. A second well lies just outside the enclosure wall, whilst several decorated cross slabs mark the sacred space, including a gabled example standing 52cm high near the north east corner of the well house. Another cross inscribed schist slab, discovered as recently as 1985, adds to the collection of early Christian stonework at the site. These elements, combined with the well house’s sophisticated construction techniques and its integration into the wider monastic enclosure, paint a picture of a significant religious site that served the spiritual needs of the local community for generations.