Currently, I am involved in cultural heritage ontology development for our local museum data to serve as metadata and the upper level semantic model. Our primary goal is to move data into linked open data cloud to enrich information about the items of our museum collections. There are several projects in this sphere already, e.g., EUROPEANA, Amsterdam Museum Linked Data, Smithsonian American Art Museum Linked Data, and so on.
If you are developing an ontology for a cultural heritage, what is the correct way to identify the existing ontoloies for items? And where to start?