Early ‘70’s I woked for NASCAR driver Elmo Langley...
After the race at Daytona kids would get big cardboard boxes from the infield concessions and climb up the banks and slide down...Tiny “marbles” from the tires on the track would allow them to go down just like snow sledding...
Cool story!
I used to live right down the road from the track and never went. :( It’s on my bucket list.