Hi Pharoers, For a project Iâm starting to prototype, I need collections where objects are inserted according to an index that is a spatiotemporal object. The idea is that each time a person add an « information" in this collection, he does it a a given place and time and I want to be able to query the collection easily according to place or time (or both). Iâm hacking it right now but I wonder if people have ideas on that subject. Iâm also interested in collection that that are indexed by the timestamp of the insertion. For the implementation of spatiotemporal classe, I choose to use a ZTimestamp and a Geolocation object. Geolocation is quite simple and is responsible among other to get the timezone, but of courses coordinates (or eventually areas). For the collection, Iâm still wandering⦠Something like an OrderedCollection with another internal array to store associated spatiotemporal(s)⦠Will hack something but Iâd love to hear others ideas. Cheers, Cédrik nb: I really think a spatiotemporal class would be interesting as a general data structure today !