the travertine cascades of pamukkale, turkey showing several storeys of pure white shallow bowls

amphitheatre archaeology autumn blue bowls calcium carbonate cascade cascades castle city civilisation columns cotton culture denizli early empire formation geology hierapolis lake landmark landscape levels limestone mediterranean minerals mountain nature outdoors pamukkale patterns pool province pure roman ruin several shallow showing sky slope snowwhite spring stone storeys summer sunshine terrace thermal tourism travertine turkey turquoise unesco upper water waterfall white wonder