These are not hotels with history in the brochure — they are buildings that carried a history before anyone thought of letting rooms in them. A royal residence, a monastery, a merchant's villa: the house is the artefact, and the hospitality is the current chapter rather than the subject.
The sensor reads the fabric. A house is admitted when the earlier building survives in a form the guest occupies — walls, rooms, proportions, grounds — and when the operator publishes what it was. A faithful reconstruction is architecture, not history, and a historic façade over an entirely new house fails the test.
The question is declared, the sensor is published, and the ground travels with the verdict.