They do appear as "Roman camp" on an OS at the right scale - try the website, where you can sign up for free for a week. Or the Heritage Gateway website mention

They do appear as "Roman camp" on an OS at the right scale - try the website, where you can sign up for free for a week. Or the Heritage Gateway website mentioned by ascorbic. There's a lot in the area that's still to be dug. It's a matter of finding the money to fund digs.