World 1-Cannon is the first world Cannon in New Super Mario Bros. Wii, and it leads to World 5. In order to unlock this Cannon, you must find World 1-3's secret exit.


The secret exit is located before the final Star Coin of the level. A Yoshi or Propeller Mushroom is needed to find it. Once Mario and Co. reach the part of the level in the image below, they must get onto the ledge (top-left) and then fly/flutter jump onto the top. The tunnel to the exit can be found by running to the right.

The secret exit is above this section of the level