Free Roam is the Mario Kart World mode that allows free exploration, with Rainbow Road as the sole exception.
In Free Roam, players can drive across the connected world rather than following a standard race route. They can travel off-road, revisit course areas, look for collectibles, complete missions, and take photographs of their selected driver.
The mode reflects the game’s wider shift from a collection of separate circuits toward a connected world. Driving between courses is important in Mario Kart World, especially in Grand Prix and Knockout Tour, but Free Roam gives exploration the main focus.
Rainbow Road is the unusual exception. Although it is a course in the game, it cannot be freely explored in the same way as the other locations. This detail is easy to miss because Rainbow Road traditionally serves as a dramatic late-game racecourse in the series.