The stairway comprises at least two steps for inter-engaging one with another, each step comprising a channel 250 through which a tensioning means 260 extends to press the steps together, a keyway 240, and a key for engaging the keyway of an adjacent step to prevent relative rotation of the steps about the tensioning means. The tensioning means may comprise upper and lower anchors between which a plurality of post-tensioned cables extend. Each step may have a plurality of channels through which one cable extends. The key may be a wedge. The key and keyway may define a snub which prevents lateral movement of adjacent steps. The steps may be cast or moulded from ultra high performance concrete. The steps may be winders such that the stairway is spiral or winding.
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