Isle Delfino
Isle Delfino is the island home of the Piantas and Nokis which Mario, Princess Peach, Toadsworth, and the other Toads travel to in Super Mario Sunshine. Some places on the island include Delfino Plaza, Shine Gate, Bianco Hills, Ricco Harbor, Gelato Beach, Pinna Park, Sirena Beach, Noki Bay, Pianta Village, and Corona Mountain. In Super Mario Sunshine, the island is full of grafitti made by Shadow Mario. Mario, with the help of the water pack FLUDD, is forced to get rid of all the paint on the island.
Later in the game, Shadow Mario takes off his suit to reveal that he is King Bowser's eighth son, Bowser Jr.. Bowser Jr. claims that, according to his father, Princess Peach is his mother.
Isle Delfino appeared again in Mario Kart: Double Dash!!. The award ceremony was held there, and the Peach Beach course also took place on its shores. Delfino Plaza is a race course in Mario Kart DS.
Isle Delfino appeared in Dance Dance Revolution: Mario Mix in the second level. It looked really different, and Toadette was the one who took care of the hotel in Sirena Beach. The hotel also looked different, and Pinna Park was a Item Shop shaped like a Pirate Bob-omb. It might be Isle Delfinom, or not.
It's called Delfino because it is shaped like a Dolphin.