The second floor of Princess Peach's Castle is an area accessed in the latter half of Super Mario 64. After collecting 31 stars and defeating Bowser in Bowser in the Fire Sea, Mario can use the key to access the second floor of the castle.
The second floor can be found past the double door located up the stairs in the main foyer. These doors lead to a spiral staircase that leads up to the second floor itself.
The second floor is a donut-shaped room with blue sky-like walls. It has many paintings which cannot be entered, except for a few: a painting of a Skeeter leading to Wet-Dry World, and a painting of Tall, Tall Mountain. There's a staircase on this floor that leads up to the third floor of the castle.
There is a door that leads to a triplet of identical paintings, all with different sizes. An example of perspective trickery has the room get progressively smaller or progressively larger, approaching the smaller and larger paintings. This leads to Tiny-Huge Island.
There is another door, surrounded with brown bricks, which leads into the infamous mirror room. This room is characterized by its large mirror, which mirrors Mario and the Lakitu filming him. There are a series of paintings in the room, although there is a bland wall that appears as a snowman painting on the other side of the mirror. This empty wall leads to Snowman's Land.
|10||Snowman's Land||In the mirror room, there is a painting that only appears on the other side of the mirror. Jumping into the wall where that painting should be will lead the player into Snowman's Land. Snowman's Land is a snowy course that has a large snowman in the center of it, that will try to blow away anyone who crosses his path.|
|11||Wet-Dry World||The first painting the player will see upon coming into the second floor, Wet-Dry World is a bizarre area with rising water levels and vile Skeeters. Delving deeper will take the player to an abandoned town beneath the water. This level is known for its strange and unsettling appearance.|
|12||Tall, Tall Mountain||The smallest painting in the second floor. Tall, Tall Mountain is a large mountain that Mario must trek up to collect all the Power Stars in the area. The trickster monkey species, Ukiki, can be found in this level.|
|13||Tiny-Huge Island||With a whole room dedicated to the three Goomba paintings, only the smallest and largest paintings can be entered. Tiny-Huge Island's gimmick is that it has two sub-areas, one where the level is incredibly tiny and another where the level is incredibly large.|
Please walk quietly in the hallway
Although isn't an actual phenomenon, the textbox's real meaning is a mystery, because the place it is in is not a corridor and walking quietly will have no effect, and neither does running or making noise.