|Notes:||Before its excavation in 1934, by Callander and Grant, the cairn was a grass-covered mound measurirg 19m by 9.7m. |
Aligned north-west to south-east, the sub-rectangular cairn now measures 15.2m long and 7.8m wide.
Access is by a passage from the south-east, 4.1m long, 0.6 to 0.7m wide, and 1.05m high. The chamber is 7.1m long and 1.6 to 1.8m wide and divided into three compartments by upright slabs. The outer compartment is 2.05m long, the central compartment 1.6m long and the inner measures 3.5m long, with 0.9m high backslab.
This large end compartment is subdivided by a pair of 0.6m high slabs across the middle. The inner subdivision has a narrow scarcement one metre above the ground, which together with a stone projecting above the north-eastern subdivisional slab seems likely to have been the support for a shelf/bench.
The walls, which showed evidence of burning, stand up to 1.8 m high at the end and up to 1 .6 m high along the sides of the chamber. Charred wood and ashes were noted on the floor, and many of the finds, including the bones, were scorched.
The remains of at least 29 human skeletons were on the floor of the passage and chamber, mostly in the two parts of the inner compartment, where the skulls were arranged along the base of the walls. The bones were mostly broken, none were articulated, and were mixed with animal bones in a similar condition.
There were flints and bone tools on the floor or immediately above it.
The chamber had been filled with rubble and earth after it went out of use. The lower filling contained animal bones and some flints, with sherds of pottery near the top. A few human bones were found in the inner compartment on a level with the scarcement.
Tombs of the Isles - Knowe of Yarso, Rousay