Good stairs are an important part of green design; you want people to use them instead of elevators in bigger buildings, and you want to get tighter, more efficient plans in smaller ones. The late great Paul Rudolph didn't have any budget or space limitations in the 1960s when he designed this stair in a townhouse on 65th Street in New York City. Architectural Digest reports that it was "commissioned by a real-estate lawyer, was later sold to fashion designer Halston, who used the living room to host bacchanals for his famous friends". It was on the market in 2012 for $38.5 million.
The Handrail Police always complain when I show these stairs without handrails, but it's interesting to see that fifty years ago architects hated handrails as much as they seem to today. And this one looks particularly problematic, in that the rise and run look way off standard. Evidently Rudolph didn't like handrails or guards anywhere;
Its most recent owner, the late German-born industrialist and photographer Gunter Sachs, replaced the wall-to-wall carpeting with white-oak floors and added balustrades on the precarious mezzanine and catwalk.
The other stair in the house at least looks normally proportioned. Still no handrail though.