Fenestrelle Fortress is the largest mountain fortress in Europe, covering an incredible 1.3 million square meters. The construction work lasted about 120 years.
The massive Fenestrelle Fortress in northern Italy is the largest mountain fortress in Europe. It covers an area of about 1.3 million square meters and is one of our top 10 sights of Italy. The fortress had the task of securing the transit route between the dominion of the French and that of the Piedmontese kings.
Construction work on the fortress began in 1728 and lasted 120 years. The fortress was left to decay for many decades. From 1984, some restoration work was carried out. Since 1990, a voluntary organization has been taking care of the preservation and restoration, but it relies on private support.
Visit to the Fenestrelle Fortress

The fortress is roughly divided into the following parts:
- Tre Denti Castle
- Batteries and field redoubts
- Delle Valli Castle
- Carlo Alberto field jump
- San Carlo Castle
Tours of the Fenestrelle Fortress

An essential part of the fortress is a covered staircase (Scala Coperta) that runs inside the fortress wall and connects all parts. The staircase is about 2 kilometers long, overcomes a height difference of 600m and counts 3,996 steps.
To visit the castle intensively there are guided tours, which must be booked in advance by phone:
- 1 hour duration
- 3 hours duration (you will see about 1/3 of the fortress)
- 7-8 hours duration (the entire fortress will be visited, sturdy shoes, sufficient water and food as well as weather protection are required - good physical condition of course)
Attention for driving on the Asietta ridge road: A driving ban applies here at times during the summer months. However, the rules are changed every year - often during the year. It is essential to observe the prohibition signs and best to inquire on site.
Best view of the Fenestrelle Fortress
A good impression of the dimensions of the fortress can be obtained by ascending the Asietta ridge road or Colle Finestre. The ascent is in the village of Depot, about 1 kilometer before the village of Fenestrelle.
If you have time, you can also cross the Colle Finestre and take an adventurous dirt road and numerous hairpin bends to the Susa Valley, where, by the way, there is another fortress worth seeing in Exilles.
Related links:
Official website of Fenestrelle
Very detailed information about the fortress by Reinhard Dietschi