A fort has existed here for millennia and the current 1830s Savoy edifice is an imposing one, set high up upon a rocky escarpment at the jaws of the Valle d’Aosta. Ride up a series of super-modern panoramic lifts, where you can admire the inspiring Alpine views and visit the Vallée Culture rooms, which offer interesting nuggets of information on Aosta’s history and traditions.
The Museo delle Alpi, a clever, interactive museum, takes you on a journey across the entire Alps – children love the Flight of the Eagle, a cinematic simulation of a bird's flight over valleys, villages, lakes and snow-capped peaks. The Museo Ferdinando details the region's military history. The fort’s prisons, which were still in use right up until the end of WWII, can also be visited (adult/reduced €5/4), and there's an excellent program of big-ticket 20th-century art and photography shows in another space.
It makes for a great day's diversion from skiing or hiking at around 70 minutes from Aosta by bus.