Postcard DE-10632103

What a wonderfully atmospheric picture of La Cote Basque and the Pyrenees! It's often easy to forget nowadays how much definition and interest are possible in a monochrome photograph. I wonder, though, what the structure to the right of the medieval-looking tower is. Could it be the glass roof of a large conservatory? And what location exactly is depicted here? The caption on the back of the card is not very specific.