RMX Bowser's Castle 1

RMX Bowser's Castle 1 is a race course in Mario Kart Tour. Unlike other remix courses, which are based on Super Mario Kart courses, this course is based on the Bowser's Castle courses from Mario Kart: Super Circuit while using the aforementioned courses' music, which is the Mario Kart 7 rendition of GBA Bowser's Castle 1's music also heard in GBA Bowser's Castle 2, GBA Bowser's Castle 3 and GBA Bowser's Castle 4. Conveyor Belts act as the main new additions of the course, but there are also returning elements such as Thwomps. The course debuted in the 2022 Bowser Tour, and was the first remix course to be added to Mario Kart Tour since RMX Ghost Valley 1 in the Kamek Tour, twenty-six tours prior.

This course is a favorite of Fire Rosalina, Penguin Toad, Mario (Aviator), Kitsune Luigi, Bowser Jr. (Pirate), Bowser (Santa), Shy Guy (Ninja), Meowser, Pink Shy Guy (Ninja), and the Bronze and Bowser Mii Racing Suits. It can also be a favorite of Chargin' Chuck (Gold) and the Dry Bowser Mii Racing Suit if they reach level 8.

Course layout
The course uses the same aesthetics as the Bowser's Castle courses from Mario Kart: Super Circuit, but with a completely different layout. This time, the course features conveyor belts as the main new course elements. Like the Bowser Castle courses from Mario Kart: Super Circuit, the course is littered with Thwomps and is surrounded by a pool of lava. All turns are sharp, right-angled turns and there are numerous jumps throughout the course, reminiscent of GBA Bowser's Castle 2 and GBA Bowser's Castle 3 specifically. The course starts on a long straightaway that contains an long, wide conveyor belt in the middle. Soon, players take a sharp left turn to reach the first set of items, before taking another left turn. Racers then drive off of the small ramps while collecting coins and avoiding the Thwomps. Then a turn to the right and follow a zig-zag path, driving along more conveyor belts as they do. Players take a slight right turn followed by a dramatic turn, before returning to the straightaway they started on, driving in a straight line until reaching the finish line. The course is somewhat similar in layout to RMX Vanilla Lake 1, albeit upside down.

This course also appears as RMX Bowser's Castle 1R (reversed), RMX Bowser's Castle 1T (with ramps), and RMX Bowser's Castle 1R/T (reversed with ramps); the former two were introduced alongside the normal variant in the 2022 Bowser Tour, while the latter debuted in the 2023 Bowser Tour.

Appearances
For this course's tour appearances, see List of RMX Bowser's Castle 1 tour appearances in Mario Kart Tour.

Names in other languages
RMX Castello di Bowser 1