Pengwern Arms, Ffestiniog, is dated 1728 and apparently always has been an inn; it was altered and extended in the early 19th century and again in the third-quarter 19th century. It was originally in the possession of the Lewis family of nearby Pengwern Hall. There are three main ranges arranged as an L; chiefly of 2 stories. The buildings are of whitened and partly stuccoed rubble with slate roofs and plain, broad chimneys. The earliest section is the stuccoed central block. In the centre is a fine recessed slate armorial plaque with the arms of the Lewis family and the inscribed date 1728.

Reference: Cadw listed buildings database.
RCAHMW, 2009.