Built at the beginning of the 2nd century AD, the Selley Theatre could accommodate around 12,000 spectators, making it one of the largest buildings of its kind. It was modified in the Gallo-Roman age. Both the orchestra and the cavea (tiered seating) are more than semicircular, the rather modestly sized stage building was built onto the exterior of the linear façade wall, and the actual stage consists of a simple wooden platform which reaches into theorchestra.
In the latter part of the 3rd century i twas finally turned into a fortified retreat enclosed by a defensive ditch and was used as such until the mid-4th century.References:
The Broch of Gurness is an Iron Age broch village. Settlement here began sometime between 500 and 200 BC. At the centre of the settlement is a stone tower or broch, which once probably reached a height of around 10 metres. Its interior is divided into sections by upright slabs. The tower features two skins of drystone walls, with stone-floored galleries in between. These are accessed by steps. Stone ledges suggest that there was once an upper storey with a timber floor. The roof would have been thatched, surrounded by a wall walk linked by stairs to the ground floor. The broch features two hearths and a subterranean stone cistern with steps leading down into it. It is thought to have some religious significance, relating to an Iron Age cult of the underground.
The remains of the central tower are up to 3.6 metres high, and the stone walls are up to 4.1 metres thick.