This splendid castle ruin is Luxembourg's largest and most dramatic. Occupying the site of a former Roman watchtower, its construction began around 1000 AD. The original belfry and inner walls still survive; the outer walls were added in 1350 and the dungeons in 1498. Restoration is ongoing but the castle will remain open. Climbing the squat, 12th-century, square keep rewards with turret-framed views over the forested river bend below. From Bourscheid village, it's a steep 1.8km descent to the east.
Admission includes a comprehensive audioguide.