The original 2 lane was 18 feet. Notice the sweet shag carpet of my old rental house
2 lanes wasn't enough. Had to double it! Also added 6 more feet.
Then took it to a pinewood derby event to let the scouts try it out.
Reduced the height almost in half to create a longer elapse race, and also keep cars from jumping.
So there it is. Haven't been able to set it up in my new place 'cause although it has more rooms, none of them are large enough to contain the 24 feet. Going to have to wait till better weather so I can set it up outside.