Milecastle 37, Bardon Mill

Milecastle 37 on Hadrian's Wall near Bardon Mill, Northumberland.
This milecastle, situated close to Housesteads Fort, contains the remains of a small barrack block.
Eighty milecastles were placed approximately one Roman mile apart along Hadrian's Wall and each guarded a gateway through the wall. The milecastle's garrison controlled the passage of people, goods and livestock across the frontier and probably acted as a customs post to levy taxes on that traffic.