The northeastern quadrant of Luxembourg—a hilly area of dense fir and beech forests, high limestone bluffs, and twisting brooks—goes by two names: Müllerthal and Le Petit Suisse. Müllerthal is the name of the river that wanders through the region. The Petite Suisse appellation comes from the resemblance to Switzerland's rolling mountain valleys. By either name the area is popular with hikers and spelunkers from across Europe.
The best place to start exploring the region on foot is the National Tourist Office (7 An Der Laach) in the little town of Berdorf, 7 km (4 mi) east of Echternach. It's well stocked with information about hiking trails and cave explorations.