Aerial photograph of Sycharth Castle, Llansilin, taken by C.R. Musson, 1993.
At Sycharth are the well preserved earthworks of a medieval castle occupying a low knoll in the base of the Cynllaith valley, below its steep wooded slopes. The castle may be as early as the twelfth century, but direct evidence is lacking. It was fullsomely, but obliquely described in a poem of about 1390 and was burnt in 1403, having no further history. This is a motte and bailey castle, consisting of a large ditched earthen motte or castle mound, 50m in diameter and 10.6m high with a 26m diameter summit, with a crescentic bailey platform, 64m across and 32m deep, on the south-west side. Excavations of a small part of the motte top in 1962-3 only uncovered evidence for two timber framed buildings, part of what the 1390 poem describes as 'a fine wooden house atop a green hill'. Further buildings, including a great lordly hall, would have stood within the bailey. The poem mentions a mill, fishponds, a warren and a deerpark containing a lodge.