Colin mainly specializes in Neolithic archaeology, architecture and monumentality and ethnoarchaeology. He has directed a series of large research projects in Orkney, initially concentrating on Neolithic settlements. The first project involved the discovery and excavation of a late Neolithic 'village' at Barnhouse in the heart of the Stenness - Brodgar monumental complex, Mainland, Orkney. This work has recently been published under the title: Dwelling among the monuments :the Neolithic village of Barnhouse, Maeshow passage grave and surrounding monuments at Stenness, Orkney (McDonald Institute Monograph 2005). The second project (Co-directed with Dr Richard Jones, University of Glasgow), continued research into Neolithic settlement on Mainland, Orkney and resulted in the discovery of three further habitation sites. Each of these, Stonehall, Wideford and Crossiecrown, runs from the early Neolithic period and in one case (Wideford) is composed of circular timber roundhouses with central scoop hearths. This research is completed and will be published in 2007 (Chambered tomb building communities in Neolithic Orkney: investigations at Stonehall, Crossiecrown & Wideford, Mainland, Orkney ).
The third project is more wide ranging (currently nearing the completion of the first phase in northern and western Scotland) and examines the construction of late Neolithic stone circles. In particular, attention is given to locating the quarries from which the massive monoliths are derived and the social processes of quarrying, moving and erecting the stones. A 'megalithic' quarry at Vestra Fiold, west Mainland, Orkney, which supplied stones for the Stones of Stenness and Ring of Brodgar, has been investigated and evidence recovered for the quarrying and moving of stones. Also, an associated megalithic tomb at the quarry has been excavated.
Investigations at the second location at Calanais (Callanish), Lewis, Outer Hebrides, has resulted in the location of quarry sites adjacent to several stone circles. Here a circle and quarry at Na Dromannan has been excavated (2003-5) and a newly discovered circle is to be evaluated in 2006. Fieldwork is also planned to be undertaken in 2006-7 at the Machrie Moor stone circle complex, Isle of Arran. This research is currently being prepared for a monograph (Monuments in the making: constructing the Great Stone Circles of NW Britain).
These research interests have also resulted in Colin being a co-director of the Stonehenge Riverside Project (with Mike Parker Pearson (University of Sheffield), Josh Pollard (University of Bristol), Julian Thomas (University of Manchester), Chris Tilley (UCL) and Kate Welham (University of Bournemouth). In this he is primarily concerned with the use of Bluestone and Sarsen in the construction of the Stonehenge monuments.
At present, after recent reconnaissance, a new project is planned (Co-directed with Dr Sue Hamilton (UCL), Francisco Torres H. (Sebastian Englert Museum), ) to investigate monumentality, the process of quarrying and 'landscapes of construction' on Rapa Nui (Easter Island), in the South Pacific. This exciting project (The social and material construction of religious monumental architecture on Rapa Nui) is planned to run for 5 years.