The inspiration for the Karka Queen's habitat in Southsun in Guild Wars Natural Rock Pools, Pamukkale Turkey. Pamukkale's terraces are made of travertine, a carbonate sedimentary rock deposited by water from the hot springs.
The thermal pools of Hierapolis: think taking a bath in an ancient pool, in sparkling water (yes, sparkling!), sitting on a piece of fallen column that was standing there in times you've studied in history books. Just amazing.