Stands on the river Rydal and Ystwith; or as the name denotes, the mouth of the Istwyth. It has a market on Monday; fairs on Monday before Easter, and December 18. It drives a good trade in fish, especially whiting, cod, and herrings; is twenty-eight miles from Cardigan, and 203 miles from London. Its old wall is almost totally decayed, as well as its castle, which had been garrisoned by Cromwell. This castle was built in 1110, burnt in 1124, and afterwards rebuilt. Near it are several ancient encampments. Great quantities of lead are dug up in its neighbourhood. The church is a handsome Gothic structure, and it has a good town-hall. The government is vested in a mayor, recorder, and common-council, &c. In 1745 ten thousand barrels of herrings were taken here; and in 1732, one hundred and thirteen bottle-noses, some fifteen feet long, which yielded great quantities of blubber, were caught among the rocks.
Llanbardarn Vawr is two miles east of Aberistwith, and 197 miles from London. It is a place of great antiquity, though much decayed, situated on the river Rydal. The town is governed by a portreeve, has a small harbour, and a market on Tuesdays.
Llanrusted, a village near Aberistwith, is remarkable for having near it two druidical sepulchres, consisting of two upright stones, one of which, when perfect, measured eleven feet in height above the ground, and five feet six inches in breadth.
Source: The Universal British Directory of Trade, Commerce, and Manufacture 1791. Volume the Fifth.
