The house-museum of P.I.Tchaikovsky in Klin, one of the oldest memorial museums in the world, is essentially a museum complex, a reserve, since it includes all the necessary components for this. The memorial house - the heart of the museum, its appearance and interior decoration, as well as the old park and manor buildings that make it whole - all this together recreates the flavor of the era, its atmosphere, and requires an extremely careful attitude. That is why the preservation and restoration of the museum complex, all its components - from buildings to every smallest museum exhibit, object, document - is one of the main tasks of the museum. During the restoration, the goal is to convey to our contemporaries and descendants the originality of the monument, remove all later layers, restore the lost elements. This huge research work is based both on thorough field studies and the museum archive.