Neil MacGregor visits Strasbourg, now in France, but also a city with a key place in German history, culture and precision engineering, as revealed by a model of the cathedral clock, now in the British Museum.

When the writer Goethe stood in front of Strasbourg's Cathedral, he discovered two things: the transporting, transforming force of Gothic architecture and one aspect of what it meant to him to be German.

Producer Paul Kobrak.