Do as the people of Luxembourg do and take in the delights of the Pétrusse Valley, which owes its name to the river separating the Ville Haute from the Bourbon Plateau. Landscape architect Édouard André truly breathed new life into this graceful, almost aristocratic valley at the end of the 19C. Here you'll come across cyclists, families with buggies, joggers (at all hours), and bankers glued to their mobile phones. A lovely spot for a stroll.