45. How many forts were there on Hadrian’s Wall?

There is no straightforward answer to this question, but the traditional list of Wall forts is (from west to east, the way the Romans listed them on the Rudge Cup etc) is Bowness-on-Solway, Drumburgh, Burgh-by-Sands, Stanwix, Castlesteads, Birdoswald, Carvoran, Great Chesters, Vindolanda, Housesteads, Carrawburgh, Chesters, Halton Chesters, Rudchester, Benwell, Newcastle, and Wallsend. That gives seventeen forts, but excluding those outwith the Vallum (Carvoran and Vindolanda) reduces the number to fifteen. Newcastle and probably Drumburgh were later additions, so the Hadrianic Wall forts can probably be numbered at thirteen.

Further reading: Breeze and Dobson 2000; Symonds and Mason 2009