The term Crannog refers to small artificial islands which can be found in the majority of Scotland’s lochs and inland waters. From the surface, most crannogs look like uninteresting mounds of stone, from which timbers sometimes protrude. These small islands were constructed and occasionally lived on by people, as recently as the 17 th century. Today, crannogs are one of the most exciting and complex sites on which archaeologists work. From research carried out over the course of the last hundred years, archaeologists have discovered a substantial amount of information concerning the form, structure, date range, and location of crannogs.

A Crannog in Loch Treig. (After Ritchie 1942)


Most crannogs are to some extent artificial. This means that it has taken a certain amount of human activity to create them. In some cases, small islands or natural bedrock outcrops were only slightly enlarged, requiring relatively little effort. In other cases, crannogs were created from scratch by piling up vast amounts of materials on the loch bed. This obviously required substantial effort and considerable time. Regardless of the effort the product is always very similar- a small island, its surface protruding above the water surface, which owes its existence to human activity. Other features which are also found on crannogs include: approach causeways from the shore, vertical wooden piles set into the lochbed, middens of discarded domestic waste, harbours and jetties.

Crannogs can take a variety of forms. Most are circular or oval, but differ greatly in size. Average surface diameters range between 15 and 30 m, although there are notable exceptions both larger and smaller. The materials used to build Crannogs vary throughout Scotland. Crannogs found in the Hebrides seem to have been built primarily of stone whereas those found in mainland were predominantly built of wood. Most of this variation has been ascribed to differences in local environments. In general, people used materials which were easy to come by or immediately at hand.

A free standing, stilt type crannog.

At the moment archaeologists believe that there are fundamentally two types of crannogs. One has a solid base and is literally an island, the other is a type of raised structure, such as a stilt house or large dock. This later type stood above the water and was substantially taller. It is often impossible to tell which type of structure a particular crannog is without excavating it.

A solid base type crannog. (After Ritchie 1942)

Evidence suggests that Crannogs have been used as habitation sites for a period longer than any other type of structure in Scotland’s history. Literary evidence indicates that crannogs were still being used in remote areas of Scotland until the seventeenth century. Archaeological excavations have shown that crannogs were used during various periods ranging from Roman times (80-400 A.D.), the Bronze Age (2000-500 B.C.), and the Neolithic (4000-2000 B.C.) This extensive time range makes it very hard to know when a particular crannog was in use.

Crannogs offer an unparalleled opportunity of recovering information about Scotland’s past. Because Scotland’s lochs are so cold, and relatively bacteria free, organic materials such as wood, seeds and plant fibre are often well preserved. Recently a 2500 year old butter dish was found underwater on a crannog site. The amazing thing was that there was butter still in it. Such superb preservation helps archaeologists piece together what life on a crannog was actually like, in a way that can’t be achieved on dryland sites. Crannogs are an important cultural resource and if properly managed they can give a unique view of Scotland’s past.