Culzean Castle (/kʌˈleɪn/ kul-LAYN, see yogh; Scots: Cullain) is a castle near Maybole, Carrick, on the Ayrshire coast of Scotland. It is the former home of the Marquess of Ailsa, the chief of Clan Kennedy, but is now owned by the National Trust for Scotland. The clifftop castle lies within the Culzean Castle Country Park and is opened to the public. Since 1987, an illustration of the castle has featured on the reverse side of five pound notes issued by the Royal Bank of Scotland.
The armoury contains a propellor from a plane flown by Leefe Robinson when he shot down a German Airship north of London in 1916.
To the north of the castle is a bay containing the Gas House, which provided town gas for the castle up until 1940. This group of buildings consists of the Gas Manager's house (now containing an exhibition on William Murdoch), the Retort House and the remains of the gasometer.
There are sea caves beneath the castle which are currently not open generally, but are open for tours throughout the summer.
The castle grounds include a walled garden, which is built on the site of the home of a former slave owned by the Kennedy family, Scipio Kennedy.
The Castle is reputed to be home to at least seven ghosts including a piper and a servant girl.