Some walks are really one building with an approach, and this is the best of them. Otto Wagner's Kirche am Steinhof of 1907 is the high point of Viennese Jugendstil — a white-and-gold church set above a hospital campus the same architect designed, on the hill where the city meets the Vienna Woods.
Three kilometres, almost all of it climbing. The honest catch is the start: no U-Bahn reaches the hill, so it's the U3 to Ottakring and the 48A bus up — check the stop before you go. From the gate of the Otto-Wagner-Spital, now the Klinik Penzing, the central axis runs straight up between Wagner's stepped pavilions, each in its own parkland.
The church is the climax, and built to be one: marble cladding, a copper dome turned green, Kolo Moser's coloured glass, even a floor that slopes to drain — designed around patients, not tourists. The opening hours are short, so plan around them; the interior is the reason you came.
From the terrace the city drops away one side and the Woods rise the other. Then the 48A back down. No loop, no trick — one great building, earned by the climb.

