Corona Mountain

Corona Mountain is the final area Mario and F.L.U.D.D visit in Super Mario Sunshine. The path to this area is opened after Mario and F.L.U.D.D complete all of the game's Shadow Mario levels. Corona Mountain is where the final showdown against Bowser and Bowser Jr. takes place. The volcano contains an area where Mario must jump across timed spiked fiery platforms. There is also an area where the plumber must steer a boat to the other side of a sea of lava. Falling into the lava results in instant death. If the boat collides with anything, it will sink into the lava. Surprisingly, although the boat is made of mud, no harm will come to it if the player avoids the obstacles. The final part of Corona Mountain is using the Rocket Nozzle to blast up onto clouds to reach Bowser's spa. Unlike the other areas, Corona Mountain does not have episodes and is merely an obstacle course, followed by the final battle.

Official Profiles and Statistics
The hot springs at the foot of Isle Delfino’s mountain is relaxing but the lava caves which open on the plaza are forbidden for public safety.

Trivia

 * In Italian and Spanish, Corona means Crown, essentially making this place "Crown Mountain." Also, the "corona" is the plasma atmosphere that surrounds the sun. That being said, it is very hot (hotter than the surface of the sun), making it possible that the extremely hot Corona Mountain is additionally (or perhaps instead) named after this corona, however the mountain is located on the "head" of the dolphin shaped island.
 * This volcano seems to be active.
 * If the player looks at the paths and platforms, he/she can see that there may have been a hallway along the level.
 * There is an enemy attack in Super Mario RPG called Corona.
 * If someone looks at Beta pictures of the Plaza you can note that the entrance of to the mountain was once covered in grass. Now it is the mountain itself.