The original 13th-century tower of Drum Castle has been suggested as the work of medieval architect Richard Cementarius, who built the Bridge of Don in Old Aberdeen. It is believed to be one of the three oldest tower houses in Scotland (and notably unaltered). A large wing was added in 1619 by the 9th laird, and further alterations were made during the Victorian era. The castle is surrounded by late 18th-century gardens, including a rose garden and arboretum containing trees from all regions of the 18th century British Empire.