The staircase at the Fifth Avenue Apple store is unusual for the chain: its a left-spiral, descending model, compared to the usual straight or spiral ascending stairs used at other stores.

The stairs are also unusual because they're wrapped around a glass-enclosed elevator, and beneath a huge, 10-meter glass cube. These annotated photos show some of the details of the stairs and the cube.
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the stair supporting
glass 		stair sidewalk the elevator and
supporting glass 		overall view
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the stair supports the support
attachments points 		close-up of the elevator
support 		view of the stair
landing
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interior of the elevator the ground floor
glass platform 		wide view of the
cube entrance 		closer view of cube
entrance
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details of the glass
cube structure