Archaeological excavations

No proper archaeological excavation took place at the Stones o' Stenness until the 1970s.

Then, following the destruction of the dolmen, a series of trenches were dug around the monument - primarily to prove, or disprove, the dolmen's historical existence.

Led by Graham Ritchie, the archaeological excavations were enlightening to say the least.

An aerial view of the Standing Stones o' Stenness, looking towards the Ring o' Brodgar.

They confirmed for the first time that the remaining stones had once been part of a circle of at least eleven stones. A twelfth socket hole for a standing stone was found, but this appeared to have been unused.

The excavators discovered that the stone ring had been entirely surrounded by a ditch, apart from an entrance gap to the north. This ditch surrounded an area 44 metres (144 ft) in diameter and two metres (6.5 ft) deep.

During the excavation, the bottom of the ditch was found to be beneath the water table and therefore kept filling with water.

This prompted the suggestion that the ditch also contained water when the henge was in use, and that the water-filled ditch was a deliberate element of the design.

The ditch was found to contain the remains of cattle, sheep and dogs, the presence of which could either indicate that offerings were thrown into it, or that the ditch was merely a receptacle for the refuse left over from the ceremonies inside the ring.

In much the same was as the dog may have been a totem animal to the users of the Cuween chambered tomb - where 24 dog skulls were found - the canine remains at the Standing Stones could imply that the dog was in some way significant to the people who used the henge.

The central fittings

At the centre of the ring was a large hearth, very similar to those found within Neolithic dwellings such as Barnhouse and Skara Brae.

Constructed from four large stone slabs, laid out flat to form a rectangle, the hearth contained traces of cremated bone, charcoal and broken pottery - finds that added weight to the theory that the monument was once a site of feasting.

Excavations at the nearby Barnhouse settlement in the late 1980s prompted Dr Colin Richards to suggest that the Standing Stones hearth had originally been on the outskirts of the village, and relocated to the centre of the ring (see right picture).

A socket hole discovered to one side of the central hearth was suggested a being home to some sort of pole - perhaps some form of "totem pole".

Moving away from the hearth, and running parallel to the entrance causeway, excavators found traces of a pair of standing stones.

Beyond these twin megaliths was a bedding-ditch that was thought to have housed a small wooden structure.

In the place where the controversial altar had been raised, evidence was found that confirmed that some form of stone structure had existed on the site, but the nature of this was not clear.

As a result, it was agreed that the two upright stones of the altar be re-erected and the "tabletop" slab left lying beside them. There they remain to this day.

Later use

In the centre of the ring a group of four pits were found, one of which was found to contain charcoal dating from between 365AD and 665AD.

This find may indicate that activity continued within the stone circle, perhaps even activity of a ritual nature, until well into the Iron Age and the middle of the first millennium AD.

Images of the Standing Stones