Nice to see a lot of recommendations for Northumberland.... so here's my list of just the 10 best places in my home county, and just outside...
1. Farne Islands, especially May/June when there are thousands of sea birds and seals
2. Lindisfarne / Holy Island
3. Druridge Bay
4. Cragside NT property, house and grounds
5. The Cheviots, and any of the wonderful, deserted valleys (College Valley, Harthope Valley, Upper Coquetdale, Breamish)
6. Beamish outdoor museum
7. Alnwick Castle and Gardens
8. Hadrian's Wall at Vindolanda, and a walk over Whin Sill past Crag Lough
9. The walk from Craster to Low Newton and back, past Dunstanburgh Castle, with a pint in the Ship Inn at Low Newton
10. Northumberlandia - the world's largest land sculpture
....although as I've written this list, I've thought of another 10!!