This stair is one of two major vertical elements of the design of the interior and, as it rises through all five floors of public space, provides a point of reference to visitors as they walk through the Davis.
One reason it's difficult to recognize the relentlessly horizontal 9/11 memorial plaza as a commemorative precinct is that the only major vertical element it contains is the misshapen pavilion designed by a trendy Norwegian firm, Snøhetta.