The valley of the Loire, one of France's major rivers, contains more castles per square inch than anywhere in the known universe. OK, I can't prove that but it just has to be true: it seems that every French nobleman who ever lived built some sort of oversized dwelling and/or hunting facility in this area, and the modern tourist is the primary benefactor. Although it's not possible to visit all of the castles on the map below, the sheer density of interesting targets makes castle hunting in the Loire Valley a rewarding adventure.
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