Staircase and Concrete Tread This topography of hills and caves guided the design of the passageways, which undulate through mysterious corridors. There's also a sculptural spiral staircase that descends into the cavernous Spa Alila.   Photo 13 of 18 in A Chinese Sugar Mill From the 1960s Becomes a Cave-Inspired Hotel

A Chinese Sugar Mill From the 1960s Becomes a Cave-Inspired Hotel

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This topography of hills and caves guided the design of the passageways, which undulate through mysterious corridors. There's also a sculptural spiral staircase that descends into the cavernous Spa Alila.