Bon Accord (motto)

The coat of arms of Aberdeen consists of three towers within a border decorated with fleurs-de-lis. This design is known to have been used on city seals from the 15th century onwards, if not earlier.

The three towers represent the three buildings that stood on the three hills of mediaeval Aberdeen: Aberdeen Castle on Castle Hill, the city gate on Port Hill, and a chapel on St Catherine's Hill. The latter two are no longer in existence, and St Catherine's Hill has in fact been levelled.

Conversely the image of a single tower, rather than the triple, is often used in the city. Notably they can be seen in the arms of Aberdeen Grammar School, Robert Gordons College, Robert Gordon University and the University of Aberdeen.

The border of fleurs-de-lis, or royal tressure as it is described in heraldry, derives from the royal arms of Scotland, and was traditionally said to have been granted to the city by Robert the Bruce as a mark of royal favour, but may only date from the reign of James I.

In 1672, the Parliament of Scotland passed an act requiring all persons or bodies using arms to record them in a register maintained by Lord Lyon King of Arms. Accordingly, the arms of the "Royall Burgh of Aberdein" were recorded in the Lyon Register on February 25, 1674. The blazon was given as: gules, three towers triple-towered within a double-tressure counterflowered argent. Supported by two leopards proper; and in an escrol above "Bon Accord"

A second shield was also recorded, based on the city's counterseal. This consisted of a temple, with St Nicholas standing in the doorway praying over a cauldron of boiling children. This was blazoned: azure, a temple argent, St Nicholas standing in the porch, mitred and vested proper, with his dexter hand lifted up to heaven praying over three children in a boiling cauldron of the first, and holding in the sinister a crosier or.

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Wikipedia