Aaron Watson Archaeology Research
These two monuments share architectural similarities with passage graves and stalled cairns, but are distinguished by the construction of two chambers on top of one another within the same cairn.
This format creates the potential for some striking effects. For example, the occupants of one chamber could have experienced sounds generated in the other, the source of which would have remained unseen. The solid stone floor dividing each would have also filtered the exchange of sound between the two levels.
Furthermore, each chamber is accessed by a separate passage from opposite sides of the mound. This means that it would have been possible for independent individuals or groups of people to access the site simultaneously.