City Geography Markup Language
OGC standard for 3D city models. Buildings, terrain, vegetation, water, and transportation.
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Where this one tends to earn its keep.
Urban digital twin modeling
Smart city planning and simulation
Building energy performance analysis
Flood and disaster risk modeling
I haven't checked this label against the actual licence text — it's the catalogue's original guess. Check the ontology's own site before you rely on it.
Others worth a look in Geospatial.