Delfino Plaza

Delfino Plaza is the main hub of Isle Delfino, lying at the Dolphin's nose. It is situated on the foot of Corona Mountain.

Super Mario Sunshine
Delfino Plaza is the main place where Mario and Peach go to enjoy their vacation in Super Mario Sunshine. This area is the largest city in the game, and has many services, varying from fruit stands to a Pianta Mario can pay to throw him into a building. The Shine Sprites mean a lot to the Piantas that inhabit the city. There is a giant Shine Sprite icon on the Shine Gate, the main gathering spot for the Shine Sprites. Cleaning the Shine Gate will eliminate the shadow around the plaza, which moves farther away as more Sprites are collected.

When Shadow Mario scatters the Shine Sprites by dirtying the island, Delfino Plaza was cast into darkness. All the inhabitants blamed Mario, and forced him to clean the entire Isle with only his trusty water pack. After Mario defeats Shadow Mario in every level, Delfino Plaza is flooded by the water of Corona Mountain's caves.

There's a large sewer system under the town, which contains Coins, 1-Ups, and Blue Coins. All the areas in the game can be accessed here, by portals, warp pipes, and even a cannon. The western side has a boathouse that makes a portal to Ricco Harbor, and inside the building is a raccon who will trade Shine Sprites for Blue Coins. Near it is a boat to the Delfino Airstrip (after Bowser has been beaten). Many side quests and Shine Sprite rewarding jobs are around the city.

Itadaki Street DS
Delfino Plaza appears as a monopoly board in Itadaki Street DS, released only in Japan. It was one of seven Mario boards that appeared in the game.

Super Smash Bros. Brawl
Delfino Plaza will be a Stage in the upcoming Super Smash Bros. Brawl. It will be one of Mario's stages. It takes place in the skies of Delfino Plaza, on a floating ship. It will soon land in the main hub, where a proper fight can take place. However, the ship will take off, and the players will continue the fight on the ship, until the next destination is reached. It will keep repeating this process until the end of the fight. Not much else has been confirmed, however.

It should be noted that a few minor adjustments to the city have been seen. The most noticeable are the two platforms mounted on either side of the Shine Gate, making that a perfect spot for a fight. Other differences are the absence of Piantas, and the disappearance of the Pianta Statue.

Other Appearances
A Delfino Plaza Court appears in Mario Power Tennis. In Mario Kart DS, Delfino Plaza was renamed Delfino Square and was a race track in the Flower Cup.

Trivia

 * Delfino means "Dolphin" in Italian.
 * Peach Beach seems to take place here.
 * When Action Replay is used to jump high into the sky, the entire Isle Delfino becomes visible, though it doesn't seem to actually resemble a dolphin.