By Date
Spacetown-2
HapyMetal 3 comments
Watt Steam-engine
HapyMetal 3 comments
Germany is famous for...
HapyMetal 26 comments
Thermite-Factory
HapyMetal 3 comments
CHALLENGE
HapyMetal 45 comments
Nuclear research facility
HapyMetal 1 comments
Firework factory
HapyMetal 5 comments
Dyson-Sphere
HapyMetal 12 comments
Laboratory
HapyMetal 2 comments
Polonium-Deuterium Reactor
HapyMetal 14 comments