64. What is the Hadrian’s Wall berm?

The berm is the space between the base of the curtain wall and the southern lip of the ditch and was usually in the region of 6m (20 Roman feet) wide, although there is some evidence that it narrowed in front of turrets. Excavation at the eastern end of the Wall has repeatedly produced evidence of pits along the berm, arranged quincunx fashion (like the 5 on dice), possibly representing the footings for entanglements made from thorn bushes and serving a similar function to barbed wire. Examples at Wallsend, Byker, Newcastle, and Throckley suggest these defences were the norm, along this part of the Wall at least.

Further reading: Symonds and Mason 2009