In the ‘50s and ‘60s skateboarding—aka “sidewalk surfing”—was severely limited due to the rough roll of metal and clay wheels. Sure, you could tic-tac down the sidewalk. But you couldn’t swoop down a steep street or fly up the vertical walls of a pool.

This changed in 1970.

East Coast surfer/skater Frank Nasworthy visited a plastics factory in Virginia that produced urethane wheels for roller-skates. Nasworthy bought a set, tried it on his skateboard—Abracadabra! The whole experience was a thousand times improved. He bought a few more sets, shared them with his skater friends, they too were blown away.

A year later Nasworthy moved to California and launched Cadillac Wheels—the name inspired by the smooth ride of the Cadillac car. They took a couple of years to catch on, but soon urethane wheels would become ubiquitous, and the performance levels of skateboarding would make great leaps forward, what with the Bert, the axle grind, the tail tap, and eventually the aerial.