Greenan Castle is a 16th-century ruined tower house, around 4 kilometres southwest of Ayr. Situated at the top of a sea cliff, it was originally a promontory fort converted into a motte-and-bailey in the 12th century. In the 15th century a tower house was built by the Lords of the Isles, which later passed into the hands of the Kennedy family.
The first known defensive structure on the site was a promontory fort, probably a fortified farmstead. Four concentric curved ditches, each around 3 metres wide, cut off the headland with the exception of a single causeway to provide access. It is not known how long this settlement was occupied, but the site was re-used in the twelfth century.
Beside the tower are traces of a walled courtyard and outbuildings, probably stables and a kitchen block, as the small tower has no kitchen within its walls.
The castle passed through various members of the clan before ending up in the hands of Thomas Kennedy, Earl of Cassillis in 1766. Around this time the residential use of the castle seems to have stopped; today the structure is a ruin.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.