What is "cilurnum"

Cilurnum or Cilurvum was a fort on Hadrian's Wall mentioned in the Notitia Dignitatum. It is now identified with the fort found at Chesters (also known as Walwick Chesters to distinguish it from other sites named Chesters in the vicinity) near the village of Walwick, Northumberland, England. It was built in 123 AD, just after the wall's completion.

Cilurnum is considered to be the best preserved Roman cavalry fort along Hadrian's Wall. The site is now preserved by English Heritage as Chester's Roman Fort. There is a museum on the site, housing finds from the fort and elsewhere along the wall.