IIRC the distance of a modern GP has to be 305Km to the nearest lap except for Monaco, but it wasn't always like that - prior to the late 60's, races were nearer the 400Km distance mark. When and why was the distance rule changed, and why to 305Km? I can't think it was due to TV constraints, as 40+ years ago the TV and advertising aspect was much less prominent in the business of GP racing. Was it to widen the gap between long distance racing and GP racing, or was it for safety reasons maybe?
The Monaco GP seems to be a special case - not only has the race distance nearly always been shorter than the normal rule, the race was reduced from 100 to 80 laps in 1968; I imagine for safety reasons as there was some thought that poor Bandini was fatigued at the time of his crash late in the '67 race. The shortening therefore took place at least a couple of years before other circuits - the Italian GP was shortened from 68 laps / 391Km in 1970 to 53 laps / 304.75Km in 1971. One wonders what the '71 result would have been if the race had gone the extra 15 laps!
Edited by nmansellfan, 04 October 2011 - 12:07.