DS Mario Circuit

Mario Circuit is the third race course of the Star Cup in Mario Kart DS. In the course, enemies appear acting as obstacles: Goombas appear crossing the road to and from the sides. By shooting a Green Shell or Red Shell at them, or using a Star, Mushrooms spawn from the Goombas. A pair of Fire Piranha Plants spit fireballs onto the course. Players will spin out of control when touching one. Regular Piranha Plants, as seen in Mario Kart 64, are also present. This track shares its music and Grand Prix introduction fanfare with Figure-8 Circuit, as well as sharing the latter with Waluigi Pinball and.

This is the first Mario Circuit to appear in the Star Cup since Mario Circuit 4 in Super Mario Kart, and is also the only nitro Mario Circuit to be the third course of a cup.

Mario Circuit returns as a classic course in Mario Kart Tour starting from the 2023 Mario Tour, and as the second course of the Boomerang Cup in Mario Kart 8 Deluxe in the Booster Course Pass.

Mario Kart DS
Characters start out the race near a lake surrounding Peach's Castle. After going through the first corner, Goombas wandering on the middle of the track will try to block the racers' path. After passing by these enemies, characters run along a piece of the lake. Due to that part having no fence, players can fall off into water. Continuing the path, two Fire Piranha Plants located in a S bend will spit fireballs to the course that will cause drivers to spin out on impact. Going through a Warp Pipe-modeled tunnel, the players reach a dirt road after taking a tight turn. The track's dirt section can cause some karts to go off of course, especially on corners. Crossing over the Pipe tunnel, the racers go down on a curly track with Piranha Plants. Past this, characters then continue running over concrete road. After taking a tight S turn, players cross the checked line.

Shortcuts
One can use a Mushroom and go behind one of the Fire Piranha Plants to cut off a turn.

Missions
Missions 5-8 and 7-4 take place on this circuit. In mission 5-8, Luigi has to race one lap on the course against Mario. In mission 7-4, Toad must get rid of 30 Goombas found in a part of the course using Green Shells from the Item Boxes.

Mario Kart Tour
This version of Mario Circuit makes its classic course debut in Mario Kart Tour starting from the 2023 Mario Tour, being announced one day after its announcement for Mario Kart 8 Deluxe. This is the first Mario Circuit course to be added in Mario Kart Tour since RMX Mario Circuit 1 in the Mario Bros. Tour seventy-nine tours prior, and is the second Mario Circuit in the game to not be, or be based on, a SNES iteration, after 3DS Mario Circuit, which was added ninety tours prior in the Tokyo Tour. The music arrangement is slightly different to how it sounded in Mario Kart DS, which makes this course the first classic course in Mario Kart Tour to receive a new arrangement for its music that is not from Mario Kart: Super Circuit; however, unlike the GBA arrangements, the theme retains most of its instrumentation.

The course has received many visual improvements since its appearance in Mario Kart DS, as well as many changes in the course. While it is mostly faithful to the layout of the original, the course is not remade in a 1:1 scale - most notably, the section after the pipe tunnel has been made far larger than its DS counterpart, and the straightaway housing the starting line is now slightly angled. The lake containing Peach's Castle, that now has the same design as in the Mario Kart Tour iteration of 3DS Mario Circuit, is noticeably smaller and now resembles a simple moat, and the roads on either side are much closer together as a consequence of this. There is now off-road between the main track and the lake. The section after the Fire Piranha Plants has now been changed into a brief forest section, and a ramp has been added at the end of the section. The wavy dirt turns alongside Peach's Castle have been changed to a more elongated S-turn, and they curve to the right first as well. More elevation has been added to the course, which is mostly noticeable with the S-turn at the end. The dirt path continues for a bit longer into the track than in Mario Kart DS. The starting banner is now designed with Mario's hat atop and features the modern Mario Kart logo.

The course also appears as Mario Circuit R (reversed), Mario Circuit T (with ramps), and Mario Circuit R/T (reversed with ramps). In the R variant, one of the Fire Piranha Plants is moved near Peach's Castle, and a trickable pipe has been added after it and before the last turn to the finish line. In the T variant, one of the Fire Piranha Plants is removed, and the ramp at the end of the forest section is replaced with a Glide Ramp.

The course is a favorite of Birdo (Red), Mario (Golf), Mario (Samurai), Toadette (Sailor), Toad (Tourist), Birdo (White), Light-blue Shy Guy (Explorer), and the Peach, Roaring Racer, Spike, Lemmy, and Ludwig Mii Racing Suits.

The internal name for this course's skybox refers to a course labelled as "N64mr". The course this abbreviation aligns with, N64 Mario Raceway, wouldn't debut until the 2023 Mario vs. Luigi Tour. Despite this, the two courses seemingly use two separate skyboxes.

For this course's tour appearances, see List of DS Mario Circuit tour appearances in Mario Kart Tour.

Mario Kart 8 Deluxe
This version of Mario Circuit returns in Mario Kart 8 Deluxe as part of Wave 4 of the Booster Course Pass. It appears as the second course of the Boomerang Cup. It is the second Mario Circuit course in the pass, after, and the third circuit course in the pass overall, after and. Despite first being announced for Mario Kart 8 Deluxe a day before its Mario Kart Tour announcement, it would debut in Mario Kart Tour before the release of Wave 4, giving this course the distinction of having the shortest gap between classic course appearances, with only a 19-hour gap; beating the previous course with this distinction,, by six days. Mario Circuit's inclusion in Wave 4 coincides with the wave's release date being near Mario Day. Due to time zones, in some regions, it is the only retro course in the series to reappear in multiple games in one day.

The course uses its appearance from Mario Kart Tour, with major visual upgrades. A Wiggler has been added to the forest section of the course - it sleeps for approximately one minute and 27 seconds before waking up and beginning to move, meaning racers are most likely to encounter it on the final lap (it can be encountered on the second lap if the 50cc class is selected, or not at all in 200cc). It walks down to where the first turn of the forest section begins, loops around in the offroad, and continues back before eventually leaving the course entirely. The forest section of the course also now has much darker grass. A set of Item Boxes outside Peach's Castle has been moved. There are less flowers outside of Peach's Castle compared to its Mario Kart Tour iteration. The spiral design on the trees' trunks has been removed. The yellow pipe after the first turn has been removed and the yellow and blue pipes near the S-turn have been made smaller to extend a fence. The minimap has been rotated by 90 degrees counterclockwise. This course is one of three in the Booster Course Pass to not have its minimap rotated so that drivers start facing straight up on it, the other two being from Wave 1 and  from Wave 4.

Internally, Mario Circuit is referred to as "Cnsw_43", implying it may have originally been intended to be the third course of the Fruit Cup.

In descriptions given by Nintendo for all of the Wave 4 courses, this course was mistakenly described with elements from Mario Circuit from Mario Kart 7, with the course being said to have "blossoming trees" (referring to the cherry blossoms in that course) and taking racers through a winding path into Peach's Castle. The course does not feature a route with "blossoming trees" or a route inside Peach's Castle; instead, a fence is present in front of the castle entrance, the castle doors are shut, and the castle bridge only comes up to the offroad.

Mario Kart DS

 * European website bio: "Constructed in the grounds of Princess Peach's famous castle, Mario Circuit is where red-capped plumbers feel most at home. Negotiate the snaking turns while avoiding waddling Goombas, bouncing flames and snapping Piranha Plants, and you might just make it to Peach's place in time for tea."

Mario Kart Tour

 * Mario Kart Tour Twitter: "The Doctor Tour is wrapping up in #MarioKartTour. Next up is the Mario Tour featuring the course DS Mario Circuit, where Goombas and Piranha Plants will try to block your path!"

Mario Kart 8 Deluxe

 * Nintendo Switch news app (UK): "Hone your defensive driving in Mario Circuit! Veterans of the Mario Kart series might remember this course from its debut in Mario Kart DS. At first glance the track around Peach's castle seems pretty peaceful, but you'll have to evade wandering Goombas and attacks from Fire Piranha Plants as you drive around it. As if that weren't enough, there are plenty of tricky corners. If you can master pulling off Mini-Turbos from drifts, they'll definitely help pave your road to victory!"

Mario Kart DS

 * Mario Kart (Trackside banners, banners)
 * Shoot!! (Trackside banners)
 * Super Mario (Trackside banners)
 * Super Star! (Trackside banners)