Cold, Cold Crevasse

Cold, Cold Crevasse is an area off-handedly mentioned in Cool, Cool Mountain, by a sign near the beginning of the level. The most common interpretation of this name is that it belongs to the slope that precedes the sign, although it does not match the description of a crevasse.

The recent boom in Super Mario 64 conspiracy theories has brought Cold, Cold Crevasse back as a discussion point, with many theorizing it to be an unused or scrapped sub-area for Cool, Cool Mountain.

Existence
There's a sign nearby the broken bridge at the beginning of Cool, Cool Mountain. On it, it reads, "Warning! Cold, Cold Crevasse Below!" and below this area is a large slope that leads downwards. It's not much of a crevasse leading some to speculate that this isn't the Cold, Cold Crevasse the sign is referring to. Considering that the name "Cold, Cold Crevasse" follows the common naming conventions for Super Mario 64 stages, it could instead be referring to a removed area erroneously still mentioned due to a developer forgetting to change the text on the sign. A crevasse is a deep open crack; this doesn't fit the description well since there is no other side that would make it qualify as a giant crack.

jefftastic's Video
As apart of jefftastic's videos documenting Super Mario 64 phenomena, one of his videos features Cold, Cold Crevasse. He seems to accidentally stumble across a warp to the area while trying to bring the penguin across the slope in Cool, Cool Mountain.

Cold, Cold Crevasse is presented as a secret area within Cool, Cool Mountain featuring only one star. The level has the player trek through the internals of a cavern, where Spindrifts are found to help the player ascend through the tower. The kind Chief Snowman signs the two signs that appear in this level. The star collected in this level is considered one of the secret stars, much like The Princess's Secret Slide. The level does not appear to be fully finished, since Mario is slowed down by snow even on non-snow parts of the stage in addition to the area being very short and partly empty.

Reportings
''Everything in this section should be taken with a grain of salt. These are all unverified claims.''

Report No. 1
I found this place when I was playing on my copy of Mario 64. I found it when I tried to do the Speedrun Strat when doing the Li'l Penguin Lost star (The one where you slide off the "Cold Cold Crevasse" and then jump back onto the platform.). However, I ended up falling. Then, it took me to this place. The happy music of Cool Cool Mountain was gone, replaced with the wind blowing. Mario landed onto the snow. I looked around to see the place was just one giant snowy platform engulfed in white fog. No enemies, no coins, no stars - nothing. I heard the "Di-ding, di-ding" (The one when you are on low health underwater) in the distance. I started running in the direction of that sound. Mario's health started falling and he started slowing down. With Mario getting weaker and weaker, my screen started getting covered in snow. When Mario finally reached the sound, he was crawling on the ground, with only one hit-point left. The source of the sound turned out to be a baby penguin. It was completely gray and it had no eyes - just black holes. Then, another baby penguin appeared. And another one, and another one, and another one. Soon, there were a total of 10 penguins surrounding Mario. A speech box came up, which said "All the players dropped us into this ravine. Join us, Mario. Be free, along with us. In heaven." The camera then zoomed onto Mario's face, who was barely alive. A smile appeared on his face, before he passed out, and subsequently died. All the baby penguins vanished into dust. Then the N64 turned itself off.

Report No. 2
(Taken from a show named "Video Game Sightings". The episode is lost media, but the transcript still exists in note form. This note was found in a old building's cabinet.)

So, you know Super Mario 64? That game? I loved that game as a middle school student, and was very excited when it came out. But there was something strange that I found in this game like a month ago. I was in Cool, Cool Mountain, and I was going to do the very popular trick where you could get to the bottom without taking the bridge. I messed it up and fell, but something very weird happened. I was in this very weird snowy-like maze thing that seemed like it would never end. I found a spindrift and attempted to jump on it, but then it just disappeared. This was the same for every enemy I came by. I attempted to defeat them, but they just disappeared before I could even land. Then I found a house structure, that while was unenterable, still was very interesting. Then I walked to the back of the house to find a penguin NPC. I talked to it and it said (scribbled in black ink, most likely to keep it a secret from nintendo). It was very interesti(rip), and horrifying. A (red ink) hidden in the (rip)? That was very interesting.

So next I tried to find the (blotch of blue paint, entire section is unreadable)

I found it and the game then told me to go to the (rip). I had no idea where that was, so I just kept wandering around. Then I found it. The place that the game had told to go to. I went inside it and (giant blotch of red ink, entire section is unreadable)

Then a screen showed up. It was very mysterious. I was not worthy? After all of this time of walking around and trying to pass through (rip), I get this screen? Is there something I was missing?

I turned off the console after that and basically have not played since then.

Report No. 3
A video was recently uploaded by Youtuber First Name Last Name documenting Cold, Cold Crevasse. The player, playing as Luigi, enters Cool, Cool Mountain and reads the sign that references Cold, Cold Crevasse before walking onto the bridge next to the sign and being warped to Cold, Cold Crevasse. The level is made up of a large rectangular box, potentially being created by Dynamic Level Arrangement, with a hallway at the beginning functioning as an entrance. There, a blue Wiggler referred to as a Snowy Wiggler in the description, appears as the only object in the level, with unique dialogue:

"Hey! This is MY house! What are you doing here? Do you want to steal my flower? My star? No! No, no, NO!"

"HEY! THAT HURT! YOU'LL REGRET THAT!"

"Ow, you're such a bully!"

"GAH! OW! UNCLE! UNCLE! Fine, take this star! And leave me alone!"

Upon defeating the Snowy Wiggler, the star flies out of bounds, and the player looks at the now miniature Snowy Wiggler, before going to the pause menu and leaving the level as static appears on the screen before the video ends.

Trivia

 * Some reports claim that the giant cavern which houses the slide sub-area in Cool, Cool Mountain once contained Cold, Cold Crevasse. After Cold, Cold Crevasse was scrapped, the hollow mountain environment may have been repurposed for the area the slide takes place in.