Westeros is one of the imaginary continents in the universe of George R.R. Martin's A Song of Ice and Fire. It is in this fictional world that the main storyline of the events of the books and the series develops. And although the bulk of the scenes were filmed in specially erected scenery, many real cities became the prototypes of fictional kingdoms. I suggest you look at the real cities and castles that became the prototypes of the kingdoms from the books and the series. Mont Saint-Michel, France – Riverrun.
Gravensteen, Ghent – Winterfell.
Marienburg, Poland – King's Landing.
Château de Chenonceau, France – Gemini.
Guaita Fortress, San Marino – Eagle's Nest.
Kenilworth Castle, England – Harrenhal.
Neuschwanstein Castle, Germany – Casterly Cliff.
Alhambra, Spain – Sun Lance.
Prince's Palace, Monaco – Storm's End.
Dunluce Castle, Ireland – Pike.
Potala Palace, Tibet – Astapor.
Hohenzollern Castle, Germany – Highgarden.
Ali Qapu, Iran – Water Gardens.
Bojnice Castle, Slovakia – Kastamere.
Lindisfarne Castle, England – Kailin Moat.
Taktsang-lhakhang, Bhutan – i ti.
Pena Palace, Portugal – Quart.
Dolmabahce, Turkey – White Harbor.
Devín Castle, Slovakia – Dragonstone.
Belém Tower, Portugal – Tower of Joy.
Washington Island, Wisconsin, USA – House of Mormont, Bear Island.
Source: vova-91.livejournal.com