Tier 1: …. usually globally recognized & revered sites:
                        Paris’ Eiffel Tower,
                        Peru’s Machu Picchu
                        Beijing China’s Forbidden City
                       Mexico's Teotihuacan's Temple of the Sun

            Tier 2: …. lack the global prestige, but are nevertheless significant sites in their
                  regions or country:
                         Italy’s Herculaneum buried at same time as Pompeii
                         France's Chateau de Cheverny in Loire Valley.

                       Tier 2 site: Chateau de Cheverny, S France:

                                                 
           Tier 3: IMO, are either uninteresting, very minor or very niche & not worth average cruisers
                        time & money. 

        b. Specialized Experiences: (French cooking class, hiking trails)

        c. Esoteric interests: Rekjavik, Iceland’s The Icelandic Phallological (penis) Museum:  Really?    
                 Really!!! �    For propriety's sake I provide a link only, leaving its pursuit up to you. �.
                                                                        https://www.phallus.is/