St. Machar is said to have been a companion of St. Columba on his journey to Iona. A fourteenth-century legend tells how God told Machar to establish a church where a river bends into the shape of a bishop's crosier before flowing into the sea. The River Don bends in this way just below where the Cathedral now stands. According to legend, St Machar founded a site of worship in Old Aberdeen in about 580. Machar's church was superseded by a Norman cathedral in 1131, shortly after David I transferred the See from Mortlach to Aberdeen. Almost nothing of that original cathedral survives; a lozenge-decorated base for a capital supporting one of the architraves can be seen in the Charter Room in the present church.
At the end of the 13th century Bishop Henry Cheyne decided to extend the church, but the work was interrupted by the Scottish Wars of Independence. Cheyne's progress included piers for an extended choir at the transept crossing. These pillars, with decorated capitals of red sandstone, are still visible at the east end of the present church. Though worn by exposure to the elements after the collapse of the cathedral's central tower, these capitals are among the finest stone carvings of their date to survive in Scotland. Bishop Alexander Kininmund II demolished the Norman cathedral in the late 14th century, and began the nave, including the granite columns and the towers at the western end. Bishop Henry Lichtoun completed the nave, the west front and the northern transept, and made a start on the central tower. Bishop Ingram Lindsay completed the roof and the paving stones in the later part of the 15th century. Further work was done over the next fifty years by Thomas Spens, William Elphinstone and Gavin Dunbar; Dunbar is responsible for the heraldic ceiling and the two western spires.
The ruined transepts and crossing are under the care of Historic Scotland, and contain an important group of late medieval bishops' tombs, protected from the weather by modern canopies. The Cathedral is chiefly built of outlayer granite. On the unique flat panelled ceiling of the nave (first half of the 16th century) are the heraldic shields of the contemporary kings of Europe, and the chief earls and bishops of Scotland.
The Cathedral is a fine example of a fortified kirk, with twin towers built in the fashion of fourteenth-century tower houses. Their walls have the strength to hold spiral staircases to the upper floors and battlements. The spires which presently crown the towers were added in the 15th century.
References:The Gravensteen is a castle in Ghent originating from the Middle Ages. The name means 'castle of the counts' in Dutch. Arnulf I (918–965), Count of Flanders, was the first to fortify this place, building a medieval bastion on this high sand dune, naturally protected by the river Leie and its marshy banks. This bastion consisted of a central wooden building and several surrounding buildings, also in wood.
In the early 11th century, the wooden building was replaced by a stone residence, consisting of three large halls that made up three storeys, connected by a stone stairwell. The monumental stone staircase, the light openings, the fireplaces built into the walls and the latrines were signs of considerable luxury and comfort in those days. There was probably also a tower.