Ravens are the largest birds in the crow family, and have a very large beak. You will probably hear a raven before you see it - they have a very deep call (cronk-cronk). I do not see ravens very often in Northumberland, they seem to be confined to the more remote areas. This one was flying around the fields near the castle, cronking. You can see in the second photo it was scattering all the Curlew.