Can I visit the castles/fortresses in the mountains around Turin, Northern Italy?

Question

Three years ago I traveled from Turin to Paris by train, and saw amazing old castles all across the mountains. Are any of them available for a visit? I'm going to rent a car so the transport won't be a problem.

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I forgot to say that I'm interested in the small castles or fortresses, not the famous ones. Something like that:

Answer 1

Check out Sacra di San Michele, about 45 minutes north of Torino:

http://www.sacradisanmichele.com/

Answer 2

Check out the Forte di Bard:

It's about an hour north from Turin, on the highway to Valle d'Aosta.

Answer 3

Here's one that you can definitely visit.

Rivoli Castle:

Cost: €6.50, free for under 11

Open: Tue-Thu 10am-5pm; Fri-Sun 10am-9pm

Answer 4

In addition to the good suggestions you already received I'd like to add:

• Forte di Bramafam: built between 1874 and 1889 it's one of the greatest fortifications of that period. It's in Val Susa, near Bardonecchia

• Forte di Fenestrelle

• Rocca di Verrua Savoia

• Batteria dello Chaberton

[I assume something like Exilles is considered mainstream and so it wasn't included in this list]

Answer 5

Most of these castles are located in Aosta Valley (Italy).
I've driven around this place and also did the Italian Job (Great St. Bernard Pass).
If you plan to visit this part of Italy, I would also recommend the Great St. Bernard Pass (closed in winter).