thumb|300px|Aesica on 1964 OS map thumb|300px|Great Chesters plan (with Milecastle 43 in red)
thumb|300px|Aesica on 1964 OS map thumb|300px|Great Chesters plan (with Milecastle 43 in red)
Aesica (modern name Great Chesters) was a Roman fort, north of the small town of Haltwhistle in Northumberland. It was the ninth fort on Hadrian's Wall, between Vercovicium (Housesteads) to the east and Banna (Birdoswald) to the west.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).