Delfino Pier is a Battle Stage only appearing in the game Mario Kart Wii. It is related to Peach Beach and Delfino Square, taking place on Isle Delfino (from Super Mario Sunshine). It takes place in a docking zone, with water surrounding the stage.
After some time, a bell will ring. After the bell rings for a couple of seconds, the water starts to slowly rise. Also, a bridge that connects lower grounds to higher grounds is lowered so that players can drive up on it. Not just this, but there are a few doors with gates that open up and allow players to enter. This area is only accessible for a few moments, noting that the water will rise and flood the room, causing the player to sink. This room is not the only area that floods. All of the lower parts of the course are completely flooded, causing racers to be forced to higher levels.