How to skate on natural ice
It made me
refreshed+tired 
"Bit worried at first but there were so many people..."
How I did it: I went first to the marshes by the Ijssel River but there was noone, they were all by the lake by Vogeleiland. I put on my artistic skates (many others had long skates or hockey skates, and many had just blades strapped to their shoes) and went down the grassy slope.
Snow on ice really slows you down and lumps make you stumble. They cleared a path which enables the ice to freeze better and that's also where it slides better, since it's blades on ice. It's not smooth like artificial of course, but it glides nicely.
I skated 6 rounds in 30 minutes, then was tired, it has been years since I used my skates. Could feel the blister coming too!
