Marine Tour

The Marine Tour was the twenty-first tour of Mario Kart Tour that began on July 1, 2020 and ended on July 14, 2020. Due to being aquatic-themed, the tour introduced Rosalina in a teal swimdress adorned with Grand Stars and Mario in his swimwear from Super Mario Odyssey as the new spotlight drivers of the tour, while also adding in fish-themed kart parts such as the Cheep Snorkel and the Manta Glider. Additionally, Koopa Troopa Beach 2 from Super Mario Kart was introduced as the signature track since its last appearance in Mario Kart DS. The menu's background featured a few islands from Koopa Troopa Beach 2 as the landmark for this tour.

Signature kart sets
In every cup, the driver which the cup is themed about is raised a tier on each track, making them a three- or two-item driver on that course. Up until the Ice Tour, a kart and a glider were also given a bonus for each race in the cup.

Rewards
Gold cells indicate rewards exclusive to Gold Pass members.

Profiles

 * Mario Kart Tour Twitter:
 * "The Peach Tour is drawing to a close in blue. Can you take the summer heat? Starting Jun. 30, 11 PM PT, these two shaded swimmers will splash and dash their way onto the track. Get ready for the Marine Tour!"
 * "It's time for the Marine Tour! Summer has come to blue, and our drivers are ready to hit the Koopa Troopa Beach for some sizzling-hot races!"
 * "The Marine Tour is almost over. Thanks for racing! Anyone up for some adventure? Next up in blue is the Exploration Tour!"

Trivia

 * This was the second tour to have a variant of a retro course appear twice and have both instances use the same icon, in this case, the Reverse and Trick variants of Koopa Troopa Beach 2, which had Mario (Swimwear) and Ice Mario, respectively, on their icons. The first tour to do so was the Halloween Tour, where both instances of the Trick variant of Luigi's Mansion had King Boo (Luigi's Mansion) appear on the icon.