The 20th century was unkind to Vienna. The capital of the Habsburg empire until 1918, it was, by early 1989, a bleak and battered outpost within touching distance of the iron curtain. Now that the city has undeniably recaptured its glory of old (symbolically, its population grew to two million last year, its pre-first world war imperial population), it might seem counterintuitive to visit it for its modernist architecture. But this is a highly rewarding endeavour, especially if one wishes to avoid an overdose of Sachertorte (chocolate cake), horse-drawn carriages, flamboyant churches and palaces, and imperial tat.