There was a roadblock of the road into the direction of Furnas.
The deviation brought us along the Castelo Branco. It is not on the maps, however.
It is not a real castle, and it is not really old either. In fact it's more a tower build to look like a donjon or something.
It just looks good!
I have not been able to find any information about it, either.
It is always open and you can go inside and climb the tower, which brings an awesome panoramic view, 360 degrees around!