You’ve spent the day exploring Vienna, one of Europe’s great capital cities. You’ve visited its wonderful museums and galleries, taken a spin on the giant Ferris wheel in Prater Park and indulged in a slice of Sacher torte at Café Central, but now it’s time to move on.

Vienna’s Hauptbahnhof (main station) is one of the continent’s foremost transport hubs. A glance at its giant departure boards offers possibilities in every direction — Rome, Warsaw, Bucharest, Kyiv, Amsterdam, Hamburg and Zurich.

Where should we go tonight?

More than any other type of train, sleepers offer a palpable sense of adventure, a journey into the unknown and the thrilling prospect of waking up somewhere far from where you started. Whether it’s Agatha Christie, James Bond, Wes Anderson’s “The Darjeeling Limited” or legendary songs by the likes of David Bowie, they’ve been a fixture of popular culture for almost as long as they’ve existed.

Overnight trains can be found on six of the world’s seven continents. And they range from deluxe hotels on wheels ferrying guests to places like Machu Picchu, the Taj Mahal or Venice in staggering comfort to the transcontinental giants of Canada and the USA with their legendary “Vistadome” panorama cars. You can cross the parched Australian Outback, thread high alpine passes or visit little-known parts of Japan’s main islands.