My wife grew up with these "spark". They are like a four legged chair on two runners. There's a wider spot on one runner to rest one foot and the other is used to kick forward. When she got this in her hands she just drifted away. It brought back memories.
We're on the ice, out in the middle of a lake: Finnsjö in West Sweden.
M4 50mm Summicron. 1/250 @ 5.6 in the flat light of nordic winter.