The test map doesn't end with the forest. The road climbs into a rocky pass, then up to the snowy highlands and the summit plaza.
After the forest the road wraps around a huge rock and hops across rock islands floating over the void. One wrong turn here and you go straight down.
The snowy section has sleds crossing the road, collapsing floor panels, shuttling platforms, a seesaw and rolling snowballs. Whoever gets past all of them enters the summit plaza, about 191 m up, through this gate.