1. Firstly, this very clean, and simple map.
2. And this larger map, of the entire world of the books.
3. An authentically old version of the world.
4. Westeros, if it had been mapped by Google.
5. This map, proving Westeros is basically an upside-down Ireland.
6. Well, unless it's actually Ireland and Britain.
7. A comparison of the size of Europe against the size of Westeros.
8. A neat comparison with Seattle.
9. This comparison that allegedly proves Westeros is actually on one of Saturn's moons, Titan.
10. The house areas, as represented by their sigils.
11. A light-hearted, but intensely detailed, look at Westeros.
12. This comparison of land holdings at the start...
14. A map explaining the original conquest by Aegon Targaryen three centuries before the events of Game of Thrones.
15. This street level map of King's Landing.
16. The population, and population density of the region.
17. Additionally, the religious plurality and ethnic plurality.
Some seriously in-depth work by Redditor scolbert08 here.