Castra Exploratorum

Castra Exploratorum was a Roman fort and civil settlement near Netherby Hall in Cumbria. It was first built by Agricola around 80 AD during the Roman conquest of northern Britain. The fort later became an outpost north of Hadrian’s Wall, about half a day’s march away. By the early 3rd century it served as the headquarters for frontier scouts. A larger garrison, Cohors I Aelia Hispanorum, arrived around 211 AD with a thousand men and three hundred horses. The fort expanded with new baths built around 222 AD and a rebuilt temple. Inscriptions show its importance during the reorganisations under Septimius Severus or Caracalla. Occupation continued deep into the 4th century, alongside four other outpost forts. The site’s strategic role kept it active long after Hadrian’s Wall was established. Today the remains lie within the grounds of Netherby Hall. Visitors can see traces of the fort’s layout and the later civil settlement. The setting is peaceful, with the hall’s estate providing a quiet backdrop. The fort’s history reflects its long service as a key northern outpost. The landscape still hints at its past importance.