Baby Park is the third track of Mushroom Cup in Mario Kart: Double Dash!!, being in the shape of an oval-shaped loop. On one side, it's blue and on the other side it's red. This presumably represents the colors of Baby Mario and Baby Luigi. It is the shortest course by far and therefore has seven laps as opposed to three.
Learning to mini-boost and snake really helps here to put an advantage over your opponents. Try to dodge or avoid getting hit by shells.
Mario Kart DS
This course reappears in Mario Kart DS as a retro course, but it only has five laps. It is one of the shortest courses, like it was in Mario Kart: Double Dash!!