The grey cairns of Camster.

The long cairn at Camster is a spectacular monument, nearly 60m long and 20m wide. It has been reconstructed in modern times, but was probably originally built in the early 4th millennium BC.

It has a curved forecourt at each end. The north-eastern forecourt is defined by a low platform and short, stepped horns. Unusually, it does not frame an entrance door.

The cairn has a long history of exploration, and prior to the first excavations in 1865–6 it had a very different profile.

Two burial chambers were found in the cairn. Both had originally formed part of separate round cairns, entered by cramped passages. Later, it seems, they were incorporated into the single long cairn we see today, though nobody is sure why. The development of the cairn and its original appearance are still disputed.