I am still adding entries to this (Facebook only as yet) heritage list. Many of the obvious ones are already there, so I am having to think carefully about new additions. It is a largely intuitive process, also informed of course by my previous research. The latest entry is the Great Wall of China, which I might have to write about separately.
So, to make explicit some of the principles I am following:
1. First of all, all places/objects on the list have to exist at present. This means that there are no Sputniks on the list: all satellites with that name have re-entered the atmosphere.
2. By necessity, the list contains both movable and immovable places and objects. No point having criteria which exclude satellites! This also means that objects like space suits and parts of things are relevant, and some of these may be in private hands, or "collectables".
3. Social significance figures highly, as with the inclusion of the Night Sky. The Great Wall of China, obviously, was not constructed with a space purpose, but is part of the folklore of space.
The good thing about the Facebook application is that I can track which ones people send to each other as gifts, so over time I think this will provide some interesting stats to play with.