I'm not sure about the history of this road but could be made by the army during the WWI. If you look closely, looks like that some kind of machine was laying stones in some kind of order. There are sides that are made of parallel installed long stones. All this is amazing as a site but not so pleasant to ride the bicycle over it. Would be better to have bigger tires and full suspension. I did struggle with 35mm tires and no suspension.
Take often brakes and enjoy the nature around you.
Enjoy and respect.