Ynys Pandy felin lechi

Ynys Pandy felin lechi is a building constructed from uncoursed but carefully jointed stone rubble, originally featuring a slate roof that was removed in 1906. It is situated on an artificial platform supported by retaining walls and consists of three storeys, increasing to four at the western end. The structure is rectangular, measuring four bays wide and nine bays long. Each bay has large semi-circular headed arches made of dressed voussoirs with keystones on the exterior, and the walls taper in thickness at each floor level to accommodate the Baltic pine floor joists, which are now missing. The eastern gable has a decorative feature around the top window.

A raised curving formation carries the original tramway to the central opening on the southern side, while incoming water flowed parallel to and outside the southern face of the building, reaching the entry point at the center. Rubbish was removed from the northern side via another tramway with a gauge of 2 feet (60.96 cm), which tipped to the northeast of the mill.

Details about the internal workings of the mill are not fully known, but it seems there was a logical progression for processing materials down through the mill. A deep cross trench at the center housed the leet that powered the main drive water wheel, with water being channeled in from the parallel channel on the southern side.