Frozen Hillside is a cold and icy course located high up in the frigid mountains. The surrounding landscape beneath the course suggests that it is located near Planet Popstar's Rainbow Resort. Most of the environment here is completely natural, such as its icicle formations and plants. But there is also some machinery present, such as the wire grating serving as platforms and even sensitive lasers scaling the walls of certain parts of the course. The course has frozen, prismatic plants and even huge whales flying around a small section of the area. There is a large cave which makes up a fourth of the course, half of which is lit solely by Dales, although there is a switch to brighten the room with what appears to be crystals along walls. Because the ground in Frozen Hillside is so slippery, Wheelies such as the Wheelie Bike or the Wheelie Scooter often skid along the course, and are not recommended.
The course itself is fairly simple. As it starts, there is a section diverter involving placing the player on an upper road and a lower road. Three platforms move up and down randomly, and if caught at the right time one of them will place the player on the upper road. Both the upper and lower roads work similarly, with differences: the upper road contains a few smooth turns left and right before it runs into a gap which the player must glide across. Following this gap is a sharp turn with no walls, which, to stay on it, involves drifting before the road ends and dumps the player in the lower road. The lower road is a tunnel with ice in the middle of it in some portions, involving the same turns and twists as that of the upper road, except without the gap to fly over. Near the end of the tunnel (once both roads end) are lasers which are shut off by the player pressing a switch in the floor with two red arrows facing each other. If the lasers are not shut off, if one of them touches Kirby he will be hurt.
Following the tunnel is four rails which lead the player up through an exhibition of a whale and various particles of ice and into the second portion of the course, during which the player enters the large cave after a short outside section involving boost pads. Inside the cave, the player can smash into ice pillars, and there is a sharp turn alongside a glamoured wall which the player cannot pass through. Another switch, with an imprint of the Swerve Star in purple, when pressed, lights up the darker section of the cave. Upon leaving the cave, there is a shaky bridge followed by a sharp turn to the right which then descends into another section below which is what appears to be some sort of bobsled slide. The player, upon leaving the slide, approaches two walls crunched together and to separate them there is yet another switch involved; this time, green with purple arrows facing away from each other. Once the walls separate, they unveil green boost pads which can be used to avoid being crushed by the walls, leading the player to the finish line which they cross to start again.