Yes - Multi-pitch sport climbing. Whenever the route exceeds the length of rope (typically 60Meters nowadays), you set up a belay station, bring up the second (belayer from below), and then begin the next "pitch".
one of the best ever. just remember: In these days, there was no support that is known of climbing of today no professional trainers no nutrition plans no climbing gyms no safety research everything had to be done just by inspiration.
Yes strength is a factor, but not a huge one. When someone is free-soloing at this level and the only thing you can mention is "strength," than obviously you are not a climber.
