Rothesay Castle is a ruined castle in the town of Rothesay on the Isle of Bute, western Scotland. One of the earliest surviving examples of a castle in Scotland, It comprises an unusual circular curtain wall built by 1230 and was later strengthened with four towers after the Norse seige of 1263.
It was further modified in the first half of the 16th century when the gatehouse was expanded and the walls heightened. It was occupied by Cromwell's army in the 17th century before falling into disrepair. Restoration work began in the 19th century and the castle is now in the care of Historic Environment Scotland.
The castle is depicted as it may have looked in around 1540.
Further reading:
https://www.historicenvironment.scot/visit-a-place/places/rothesay-castle/
https://en.wikipedia.org/wiki/Rothesay_Castle
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