This is the tomb which, following its excavation in 1949, became the type-site for the Bargrennan style of chamber tombs.
There are around a dozen of them in SW Scotland and the distinguishing feature is a chamber which is structurally indistinct from the passage. This sets them apart from the more numerous Clyde tombs whose distribution overlaps that of Bargrennan tombs.
Bargrennan tombs can be set in round or long cairns.