Penisarwaun, a hamlet in the parish of Llanddeiniolen, county Gwynedd, 5 miles south east of Caernarfon.
[From The National Gazetteer of Great Britain and Ireland (1868)
"LLANDDEINIOLEN, a parish in the hundred of Is-Gorfai, county Carnarvon, 4 miles N.E. of Carnarvon, its post town, and 6 from Bangor. It is situated at the head of the vale of the Cegid to the N.W. of Snowdon, and E. of the Menai Straits. The parish, which is very populous, includes the villages of Clwt-y-Bont, Ebeneza, and Penisarwain. The old Roman road passes through it. The people are mostly employed in the Dinorwig slate quarries. There are several mineral springs. The tithes were commuted in 1839. The living is a rectory* in the diocese of Bangor, value £305, in the patronage of the lord chancellor. The church is a small ancient structure. The parochial charities produce about £6 per annum. In the neighbourhood are some objects of antiquarian interest, including a rocking stone, a Druidical circle, and cyttian, the ruins of the palace of Llewelyn ap Grufydd, the last of the princes of North Wales, at Llys Dinorwig, and the pass of Nant-y-Garth, through which it is said Archbishop Baldwin and Giraldus passed in 1118."
Near the church are some ancient yew trees, one of which is nearly 30 feet in girth, and a little to the N.E. is the famous camp of Dinas Dinorwig, supposed to be of Roman origin, and the largest fortified post in Carnarvonshire. It is surrounded by a double entrenchment, with a lofty bank between the ditches, and is of an oval shape. Here, too, is the Flynon Cegin Arthur well, at the Cegin's head. At Penllyn lived Margaret Uch Evan, "the queen of the lakes," a woman celebrated in Welsh story as the best hunter, fisher, wrestler, and musician in all Wales. Brintirion and Vaenol are the principal seats."