And it's a hard rain that's gonna fall....Freeman Dyson's wonderful concept spacecaraft, "ORION."
Propelled by atom bombs. I forget the base plate specs, but the idea was to sling nuclear warheads under a hugely thick steel/cement disc upon which the spacecraft was mounted with shock absorbers. A hundred or so nuclear detonations later, you have a city-sized vessel in orbit.
Would (in theory) do less environmental damage than the world's internal-combustion vehicles.