Constructed as a tower house in the late 14th century, Crichton Castle was expanded as power of the Crichton family grew. However, the Crichtons fell from favour in the later 15th century, and the castle passed to the Earls of Bothwell. Francis Stewart, 5th Earl of Bothwell, constructed the Italianate north range in the 1580s, featuring an elaborate diamond-patterned facade. After Bothwell was accused of witchcraft the castle fell into neglect. The ruins are now in the care of Historic Environment Scotland, and are open to the public. A mile to the south-west is Borthwick Castle, a 15th-century tower house that is still in use.
The castle's most distinctive feature is its Italian-influenced courtyard façade, which forms part of the north range. Francis Stewart, the designer, had travelled to Italy, and was inspired by new styles and technology in buildings there, particularly the Palazzo dei Diamanti in Ferrara (c. 1582). This was the source of the diamond rustication on the courtyard wall. The initials of Francis and his wife Margaret Douglas appear on the walls, together with an anchor representing Stewart's position of Lord High Admiral of Scotland. Inside are further innovations: Scotland's first 'scale-and-platt' stair, i.e. a modern-style staircase with landings and a drawing room to the north of the old tower.
To the south of the castle is a large stable block, with a horseshoe-shaped window and lodgings above.
References:The Citadelle of Quebec is an active military installation and official residence of both the Canadian monarch and the Governor General of Canada. It is located atop Cap Diamant, adjoining the Plains of Abraham in Quebec City. The citadel is the oldest military building in Canada, and forms part of the fortifications of Quebec City, which is one of only two cities in North America still surrounded by fortifications, the other being Campeche, Mexico.
The first fortifications in Quebec were built by the Governor General of New France Louis de Buade, and completed just in time for the Battle of Quebec in 1690.
After the British conquest in the second half of the 18th century, the problem of Quebec City's defences grew more acute.