Heidelberg

The university was founded in 1386, and the castle above the town was wrecked by the French in 1693 and then deliberately left as a ruin — nineteenth-century Romantics, Turner among them, considered it improved. The Philosophenweg on the far bank was the professors' walk, and the student prison, in use until 1914, has walls covered in the self-portraits of those confined for duelling and disorder.