Do they use real castles in Game of Thrones?

Related questions

1. Who took daenerys dragons in Qarth?
2. Who kills Jon Snow in the books?
3. Who killed Stannis Baratheon?
4. Is Hermione a witch?
5. Does Daenerys go to Westeros?
6. What are the Bloody Mummers?
7. Did Doreah betray Daenerys?
8. Is Sons of Anarchy based on Hells Angels?
9. Why did khaleesi walk into the fire?
10. Who betrayed Daenerys?

Tags

1. #iceland
2. #forests
3. #filmed
4. #dozens
5. #scenes
6. #castles
7. #mountainsides
8. #across
9. #europe
10. #fantasy
11. #world
12. #place
13. #thrones
14. #craggy
15. #takes
16. #medieval