My school had a set of ~7 meters high monkey bars, it was so long kids had to slide down the vertical support posts, only a few were brave enough to climb on it and even fewer had the strength to reach the end. It was demolished in 00s.

The other crazy piece of equipment I never saw again were these swings. Unlike ordinary swings where you just sit and oscillate 120 degrees, with these, you had to hang from the hand holds, the rotation was not limited by the top bar and could rotate 360 degrees (some regular swings had that too, though). The swings were symmetrical and counterbalanced, so two people could swing at the same time on the opposite sides, the design encouraged rotation instead of swinging, lifting you about 3 meters high. My classmate broke both her arms on these, soon after the swings were removed.

I never played on either.

Mine too! They were set upright (like they are on a vehicle) and partly buried in the ground. Kids would crawl in them and just hang out in the cool shade inside. There were 3 tires, one was definitely "the best", and you had to be fast if you wanted to get any of them!

I remember that those big tires were 1) fun to climb on, and 2) an early and lasting lesson that things get really hot when sitting out in the sun, and that sometimes things feel cold before you realize they are burning the living fuck out of you.