The central part of the old town is a conservation area rich in historical buildings, some dating to the Middle Ages, and many vernacular buildings of the 17th-early 19th centuries built in the locally ubiquitous grey granite. A notable feature of the later buildings is the early use of hand-made bricks to build up gables, top garden walls, etc.; this use of brick being rare elsewhere in Scotland before the late 19th century. A number of the streets remain paved with stone setts. There are also several university buildings from the late 20th century.