Aerial view of Monday Cleugh Iron Age hillfort. Photo © Tim Gates.

This Iron Age hillfort is on the south west and west slopes of Harehope Hill. It sits on level ground at the head of a deep crag-sided hollow, known as Monday Cleugh. The enclosure is semi-circular in shape and measures 138m north-south and 101m east-west. It is surrounded on three sides by earth and stone banks, but on the east side the crags provide a natural defence. The ramparts still survive, in places to a height of 1.2m. In many places kerb stones are still visible along their edges. There are two main entrances: an opening in the south-east corner and another in the west side. The turf-covered remains of three huts are visible within the enclosure, with very low standing walls. A larger rectangular foundation (6m x 19m) can be seen close to the west entrance. Other similar rectangular foundations can be seen attached to the outer rampart.. In the medieval period a number of sheepfolds were build over the remains of the fort, and the rectangular buildings may relate to this period. This is a Scheduled Monument protected by law.