The Eglinton Castle estate was situated at Irvine, on the outskirts of Kilwinning, North Ayrshire, Scotland (map reference NS 3227 42200) in the former district of Cunninghame. Eglinton Castle, was once home to the Montgomeries, Earls of Eglinton and chiefs of the Clan Montgomery. Eglinton Country Park now occupies part of the site.
There are more than 20 Earls of Eglinton.