Vanish Cap Under the Moat is a secret course in Super Mario 64 that is accessed through the moat outside the front of castle, after the water in the moat has been drained. To do so, Mario must ground-pound the pillars, then go out to the newly-exposed door. He will find a hole near the waterfall that will wrap him to the course. It was renamed "The Secret Under The Moat" in the remake, Super Mario 64 DS. It consists of a massive slope at the start, 8 Red Coins, several moving platforms, and the switch that activates the Vanish Cap. The switch is located at the end of the level. If the player falls off, the player will exit from a hole near the moat and not die.
In the DS version, the player has to collect all eight red coins over the obstacles with all three plumbers. Using Luigi's cap, then a power flower, in place of the Vanish Cap, Wario can go through the gate and get the star. And also a new area was added where the second star is. He can grab Mario's Cap to float to the new area step on the star switch and use the two power flowers again or wall jump.
In SM64DS, only Wario can start the course because it is under the large black brick blocks which only he can destroy.