The site, at the Furness village of Urswick, is the first Roman fort to be found in the area.

Steve Dickinson believes it could turn out to be the missing fort of Bannaventa Berniae, which is believed to be where St Patrick was born.

His team will spend the summer investigating the site.

Mr Dickinson said: "Forts are two a penny around Carlisle, you can dig a hole in a field and find one, and there's Hadrian's Wall of course, but down here there's a big gap where no forts have previously been discovered, so it really is a significant find."

He also hopes it will back up his belief that St Patrick was born in the area.

"Nobody will accept this theory until we end up with a bit more evidence, inscriptions and so forth, but we have got all the rest of the summer to look at the site.