Dun Mor (grid reference NM04234927) is situated on a rocky knoll on the northern coast of island of Tiree, about 1 kilometre northwest of the hamlet of Vaul.

[2] After an interval of unknown duration (possibly several centuries) the knoll was reoccupied and the construction of the broch and its outworks began.

[2] Before long the upper storeys of the broch wall were demolished, and a round house (or an aisled wheel-house) was constructed within the interior.

[2] It seems the broch was abandoned in the mid 3rd-century, the latest datable artefact from the interior being a fragment of a Roman glass bowl made in the Rhineland between 160 and 250 AD.

[2] The finds include large quantities of native pottery sherds; fragments of Roman glass and samian-ware and coarse-ware vessels; bronze and silver spiral finger-rings; rotary querns; quartzite strike-lights; glass ring-beads; tools and dice of bone; and several tools used in weaving and the working of metals.