Desmond Castle stands on the north bank of the River Maigue, guarding the ford that gave Adare its name. It was first mentioned in 1226 and is said to have been built inside an older ring fort. Most of what survives was probably built by the Kildare FitzGeralds, who held it until 1536, after which it passed to the Earls of Desmond, whose name it carries.
The castle has been under restoration since 1996. You can't just walk up to it: visits are by guided tour only, from June to September, with tickets and a shuttle bus from the Adare Heritage Centre on Main Street. Adult tickets were €10 in 2024.