One of the most spectacular train rides in the world, the Petit Train Jaune runs between Villefranche-de-Conflent and La Tour-de-Carol (with onward links towards Toulouse or Barcelona) in the upper Cerdagne and is a wonder of early twentieth-century engineering. Built to link up the villages of the high Pyrenees with Perpignan, the antique narrow-gauge carriages now mostly carry tourists, cyclists and skiers. The most spectacular section of the route is in the upper Têt between Olette and Mont Louis where you’ll trundle over gorges and massive viaducts. The summertime frequency of the trains makes it practical to hop off and on, allowing you to explore the areas around smaller, isolated stations, many of them haltes facultatifs (ask to be set down). Outside summer, the timetable is somewhat unreliable, as the aging train system needs regular maintenance.