Was built by David Roberts and Sons, Brewers.
1912 – Wales Trades Directory 1912 – Castle Hotel, South Road, D. Wells, proprietor.
1918 – Trade Directory Wales – 'Castle Hotel, South Road, facing the sea, first class family and commercial, excellent accommodation for visitors. Mrs A. E. Moule, proprietress. (late of the Roebuck Hotel, Kidderminster).'
1920 – According to Kelly's Directory 1920 the landlady was Mrs Annie Moule.
1923 – Aberystwyth Guide – advert – 'Castle Hotel, South Road. Well equipped and comfortable. Proprietress : Mrs A. E. Moule.'
1926 – Wales Trades Directory – 'Castle Hotel, South Road (near castle and sea). P. Bunting, proprietor.'
1939 – Wales Trades Directory – Castle Hotel, South Road.
1971 – Aberystwyth : sun, sea, scenery – advert (with photographs) – 'Castle Hotel, South Road. Tel : 7392. Proprietress : Mrs Carole Rowland. First class fully licensed hotel. H. and C. Electric fires and shavning points. Residents' loundge, Harbour Bar and Castle Dungeon Bar. Bed and breakfast. Packed lunches on request. Special terms for children. Private sea fishing trips arranged. There's always a welcome at the castle.'