On this treeless square, books by Brecht, Mann, Marx and other ‘subversives’ went up in flames during the first full-blown public book burning, staged by the Nazi German Student League in 1933. Michael Ullmann’s underground installation, Empty Library, beneath a glass pane at the square’s centre, poignantly commemorates the event.

Named for August Bebel, the cofounder of the Social Democratic Party (SPD), it was called Opernplatz (Opera Square) when first laid out in the mid-18th century as part of the Forum Fridericianum, a cultural centre envisioned by Frederick the Great. Money woes meant that only some of the buildings could be realised: the Staatsoper Unter den Linden (National Opera House, closed for restoration until 2014), the Alte Königliche Bibliothek (Old Royal Library), a palace for Fritz’ brother Heinrich (now the Humboldt Universität), and the copper-domed Sankt-Hedwigs-Kathedrale.