I'm a sucker for thesebefore/after VFX reels that special effects houses like to put out, and this Game of Thrones deal is no different. Some pretty large spoilers in here:
The point of these demonstrations is to show off what's been digitally added, but in this particular instance I'm way more impressed by the volume of set pieces that are real. Castles, cliffs, and camps - an alliterative cornucopia of meat-space locations. This show has got to cost a fortune to produce. Money well spent.