Hadrian’s wall: the northmost edge of the Roman Empire

At the top of the outpost line, we reach the rest of what is known as a ‘milecastle’, a rectangular blockhouse typically placed along the empire’s various frontiers (limes) acting as an additional defence post.

Throughout the Wall, the Roman legions built 80 milestone castles (spaced about a mile apart, hence the name ‘mile’) and 158 turrets. This particular fort is known as Castle Nick, or Milcastle 39, because of the numbering that follows from east to west along the entire wall.

This spacing allowed for effective organisation and control over the entire perimeter of the wall. Indeed, in the event of an attack, each relevant milecastle could quickly send troops (stationed in the latter) to defend the wall without having to cover unreachable distances. This manoeuvre speed ensured an effective response time, which was essential to repulse enemy attack attempts.

The dimensions were different, but generally, they were about 15 by 18 metres (16 by 20 yards), with stone walls up to 3 metres (10 feet) thick. The height was probably 5-6 metres (16 by 20 feet) to match the size of the adjacent wall.

The milestone castle built along Hadrian’s Wall (with a few exceptions) protected a passageway at a causeway that crossed the moat to the north of the fortification. Within the castle was probably stationed a garrison of about 20-30 auxiliary soldiers housed in two blocks of barracks. On either side of the milecastle stood a stone tower (turret), located about a third of a Roman mile, about 500 metres (550 yards) away. It is assumed that the garrison also provided soldiers to guard the turrets. In addition, it controlled the possible passage of people, goods and livestock across the border and supposedly acted as a customs house to impose duties on this traffic.

This castle offers a magnificent example of what the original Roman organisation was, one of the strong points that allowed Rome to expand into these desolate lands.

The path leads to the next point, showing the uniqueness and wonder of the curious Sycamore Gap Tree, a truly outstanding view.