Cysulog is a well preseved mid C17 farmhouse with rare date panels for both 1650 and 1652. The attached cartshed probably dates to the early C19 and around this time, the house was re-arranged internally with the addition of the wooden dogleg stair. The house was probably used as a farm outbuilding after the construction of the new house circa 1900 .
The house is a one-and-a-half storey mainly stone built property, with slate roofs and some weatherboarding. The house has a large rectangular stone chimney to the right and a gabled dormer. On the grounf floor, there is a boarded door to the left and a window to the right with later doorways in the left gable end. The right side of the house is linked to the cartshed by an extending roof to form a covered open bay. The lofted cartshed consists of a block of two bays with a weatherboarded upper storey with two small windows. There is also a stone stair leading up to a doorway with a boarded door at loft level.
Source:- Cadw listed buildings, NJR 08/09/2008