Is this worth a detour to see?if yes pls explain, and any recom budget lodging nearby?
JS, you're digging deep. Where are you finding these places? Answer: If you're in the area, sure--but it depends on where you are that day, and what your other choices are. Here's a website http://www.smithsonianmag.com/travel/Endangered-Cultural-Treasures-Fenestrelle-Fortress-Italy.html
Neat, I just got that issue of the Smithsonian in the mail today, but I've never heard of this fortress before. It looks like a wonderful diversion off of another trip. I have no idea about lodging, but thanks for posting!