Vienna was the capital of an empire of fifty million people. In 1918 that empire dissolved and left a city of two million governing a country of six — a head without a body, as the phrase went. Almost everything visitors come to see was built for the larger job.
The shape of it
The Innere Stadt, the first district, is the medieval and Baroque core, about a kilometre across. Around it runs the Ringstrasse, built from 1857 on the line of the demolished city walls and lined deliberately with the institutions of a liberal empire: the Opera, the twin museums, the parliament, the Rathaus, the Burgtheater, the university. Walking or riding the Ring is the fastest way to understand what Vienna thought it was.
Outside the Ring, districts 2 to 9 form the inner belt. Outside those runs the Gürtel, a second ring road on the line of the outer fortifications, and beyond it the districts numbered up to 23. The 2nd and 20th sit across the Danube Canal; the 21st and 22nd are across the Danube proper.
The numbers spiral outward and are used constantly. Postcodes encode them: 1070 is the 7th.
The water
Two waterways matter. The Danube Canal is the small one that runs past the old town and is the city’s inner edge — bars, graffiti, cycle path. The Danube itself is a kilometre further out, straightened in the 1870s after repeated floods and given a parallel relief channel in the 1970s. The spoil from that channel made the Donauinsel, a 21-kilometre artificial island that is now the city’s beach, festival ground and swimming water.
Scale
About two million people in the city, 2.8 million in the metropolitan region — roughly a fifth of Austria. It is a compact capital: the centre is walkable end to end and the U-Bahn reaches anywhere a visitor needs in under twenty minutes.
Around a third of residents have a migration background, chiefly from the former Yugoslavia, Turkey, Germany and more recently Ukraine and Syria. Vienna is not the monoculture the Baroque façades suggest.
Housing
The single most distinctive thing about the modern city. Around six in ten Viennese live in council or subsidised housing, a direct inheritance of Red Vienna in the 1920s. It is unstigmatised, mixed-income and permanent, and it is the main reason Vienna keeps topping liveability tables.
Language
German, in an Austrian variety with its own vocabulary — Erdäpfel not Kartoffeln, Paradeiser not Tomaten, Jänner not Januar. Viennese dialect is a further layer and is affectionately impenetrable.
English is widely spoken in the centre and among younger people. Grüß Gott is the standard greeting, Servus the informal one, and Danke will get you further than you expect.