The Karl-Marx-Hof is a single building over a kilometre long, and less than a fifth of its site was built on. Stand on 12.-Februar-Platz and the centre of it rises into six towers over wide arches, ochre and iron-oxide red. Vienna's Social Democratic council put it up between 1927 and 1930 to plans by Karl Ehn, a pupil of Otto Wagner. The 1,382 flats were small, about forty square metres: a living-kitchen, one room, running water, their own lavatory.
None had a bathroom. You washed in one of the two bath houses and did the laundry in one of the two laundries, because the plan was to move housework downstairs, next to the kindergartens, the library and the pharmacy. In February 1934 the federal army brought artillery against the block during four days of civil war, and it gave in on the fifteenth. On 14 June 1938 the Nazis began clearing Jews out of Vienna's council flats, and the 212 Jewish residents here were given two weeks to go; a plaque names the forty-six who were murdered.