Silo: Generic/unknown
Resource and Industrial
Tower: Clearance
Tower: Communication
Tower: Control
Tower: Lookout
Building: Barn/machinery shed
Other
Building: City hall
Government and Institutional
Building: Dome
Building: Electric power station
Building: Fire station
Emergency
Building: Grain elevator
Building: Religious building
Parabolic antenna: Radar
Parabolic antenna: Radio telescope
Ruins: Generic/unknown
Culture
Building: Other