I was given push-along blue rail train set 171 for Xmas in 1978. Imagine controlling your own railway at age 5 then! (I grew up next to a real railway and toys weren't, and still aren't, that sophisticated for my [then] age group). I was gotten from then until about age 15, some 10 years later, as the range evolved and expanded. Haven't looked at Lego for years, but remember doing isometric drawings in pencil of trains I would build if I could at the time.
Cheers,
IFC