Ha ‧ dri ‧ an's Wall /ˌheɪdriənz ˈwɔːl/ BrE AmE
a stone wall which the Roman ↑ emperor Hadrian ordered to be built across the north of England in 122 AD from the east coast to the west, in order to defend Roman Britain from attack by northern tribes such as the ↑ Pict s . Part of the wall and some of the ↑ fort s built along it can still be seen.