Bebelplatz

In front of you is Bebelplatz, one of Berlin's most harmonious squares and also one of its most powerful places of remembrance. Look for a pane of glass set in the ground in the middle, and peer in.

1Frederick the Great's forum

In the mid-18th century, Frederick II wanted a grand forum for the arts and learning here. Georg Wenzeslaus von Knobelsdorff built the Opera, which opened in 1742. At the back rose St. Hedwig's, the Catholic cathedral inspired by the Pantheon in Rome. And to the west stands the Old Library, which Berliners nickname “the Chest of Drawers” because of its curved façade. Across Unter den Linden is Humboldt University.

2The night of the books

On 10 May 1933, Nazi students burned some 20,000 books on this square, by authors branded “un-German”: Heinrich Mann, Erich Kästner, Sigmund Freud and many others. Joseph Goebbels gave a speech in front of the bonfire.

Beneath the glass is the “Library” memorial by the Israeli artist Micha Ullman, unveiled in 1995: a white room lined with empty shelves, with space for about 20,000 volumes. You can't go in. You can only look at what's missing.

“That was only a prelude: where they burn books, they will in the end burn people too.” Heinrich Heine, Almansor (1821)

Heine wrote those words more than a century earlier. Today they can be read on a plaque beside the memorial.

3What to look for

• The empty shelves beneath the glass; at night they're lit up.
• The plaque with Heine's quotation, set in the ground.
• The curved façade of “the Chest of Drawers”, on the west side.