This is a glossary of terms commonly used for the components of Hadrian’s Wall.

Berm – the area between the southern lip of the ditch and the north face of the curtain wall.

Berm obstacles – pitfalls placed in a quincunx pattern along the berm, so far only noted in the eastern sector.

Branch Wall – short length of curtain wall that ran down from the south-east corner of Wallsend fort to the River Tyne.

Broad Gauge – the original form of construction for the stone curtain wall, 10 Rft (c.2.9m), succeeded by the Narrow Gauge

Clay bonding – a Roman military construction technique that used clay, instead of lime mortar, to hold the core and faces of the curtain wall together. To be effective, it needed to be at least pointed with mortar, if not completely rendered.

Counterscarp –the artificially raised northern lip of the ditch, formed from upcast from the excavation of the ditch.

Curtain – the stone wall that comprises the body of Hadrian’s Wall.

Ditch – a V-shaped trench running to the north of, and parallel with, the curtain wall for most of its length (there are interruptions in the central sector where steep crags render it unnecessary).

Crenel – the gap between two merlons on a parapet.

Crenellationsparapet formed from alternating crenels and merlons.

Fort – fortification usually housing an entire regiment, in the form of a cavalry ala, an infantry cohors, or a mixed cavalry-and-infantry cohors equitata. usually around 500 men, sometimes as high as 1,000. Included gateways.

Gateway – there were passages through the curtain wall at every milecastle and fort, where main Roman roads crossed the route, with occasional extras (as at Knag Burn).

Intermediate Gauge – at 8.5 Rft (2.45m) narrower than Broad Gauge, broader than Narrow Gauge, used after the return from the Antonine Wall to replace the Turf Wall.

Merlon – the highest part of the parapet, with a crenel to either side.

Milecastle – a fortlet placed every Roman mile along the line of the curtain wall, with a gateway through the curtain wall.

Military Road – 18th-century road constructed between Newcastle and Carlisle which is in part on the line of Hadrian’s Wall and which used material scavenged from it.

Military Way – the Roman road that ran behind the curtain wall and north of the Vallum, and linked the turrets, milecastles, and forts.

Mortar – Roman mortar was made using quick lime (from burnt limestone), sand, and water. Initially used sparingly on the curtain wall, the Severan rebuild saw it regularly employed.

Narrow Gauge – the later form of construction for the stone curtain wall, 8 Rft (c.2.3m), succeeding the Broad Gauge

Parapet – the breastwork that may have topped the curtain wall if a walkway was incorporated.

Stanegate – a road running between Corbridge and Carlisle (and possibly beyond) that pre-dated the Wall system but came to be integrated into it.

Turret – the towers placed every third of a Roman mile, two between each milecastle normally.

Vallum – modern name for the linear earthwork to the south of Hadrian’s Wall, comprising a central flat-bottomed ditch flanked by shaped upcast mounds to the north and south.

Walkway – the platform that may have topped the curtain wall and been protected on the north side by a parapet.