4+ HOURS of Unexplained Deep Sea Mysteries

The ocean is deep, dark, and full of mysteries we may never solve. From lost cities beneath the waves to ships that vanished without a trace—these true stories will leave you questioning what lurks in the deep.

In this 4+ hour deep-sea mystery documentary, we explore real unsolved ocean mysteries, including the Yonaguni Monument, ghost ships like the MV Joyita, the Ningen, the Devil’s Sea disappearances, and the mysterious sounds of the Mariana Trench. From sunken lost civilizations to strange underwater creatures and legendary vanished vessels, join us as we dive into the deepest, strangest mysteries of the ocean.

Intro - 00:00
Yonaguni Monument - 00:48
Disappearance of the MV Joyita - 13:54
Mystery of the Challenger Deep - 27:55
Sunken City of Heracleion - 47:13
Disappearance of the San Juan - 1:03:39
Unexplained Depths of the Dragon Hole - 1:18:49
Antikythera Treasure - 1:32:21
Ghost Ship Mary Celeste - 1:40:36
Lost City of Pavlopetri - 1:56:33
Disappearance of the USS Cyclops - 2:13:02
Fate of the Waratah - 2:24:49
Phantom Submarines of WWII - 2:42:46
The Kaz II Mystery - 2:57:55
Treasure of the Flor de la Mar - 3:11:55
Mystery of the Devil’s Sea - 3:27:15
Ningen & Deep Sea Gigantism - 3:41:50

To support what we do and get access to ad free videos, become a Patreon member below:

DISCLAIMER: The pictures, audio, and video used in the videos on this channel are a mix of paid stock, by attribution, royalty-free, public domain, or otherwise fall under the guidelines of fair use. No copyright infringement is intended. All rights belong to their respective owners. If you are or represent the copyright owner of materials used in this video and have an issue with the use of said material, please contact me directly. I will respond immediately.

As images and footage of actual events are not always available, Uncharted Mysteries sometimes utilizes similar historical images and footage for dramatic effect. I do my best to keep it as visually accurate as possible. All content on Uncharted Mysteries is researched, produced, and presented in historical context for educational purposes. We are history enthusiasts and are not always experts in some areas, so please don't hesitate to reach out to us with corrections, additional information, or new ideas. -

[TheUnchartedMysteries]

If you’d like to support our small channel and help us keep making more deep-dive mysteries, consider becoming a Patreon member! You'll get ad-free access to all our videos and exclusive Patreon only content. Every bit of support means the world to us. Join here:

[Giggletooshy]

I tried to fall asleep to this, but got so excited to hear more than I accidentally ended up staying up until 3am haha Great content, brother!

[beargrizzles]

The anxiety the marianna trench gives me is unparalleled. I dont know why, but I've always been horrified at the thought of just floating over it. I'm not scared of water or the ocean. I have a healthy amount of respect for it. The marianna trench is just a whole other beast.

[FullofSouthernCharm]

As someone who suffers from severe insomnia these videos are the perfect medicine and your voice is icing on the cake!

[putalimura]

Secrets of The First Order isn’t just another book about secret societies—it’s a dangerous weapon. The kind of book they would bury if it ever got too much attention. Every chapter digs deeper into the hidden forces that have shaped our world from behind the scenes. What shook me most wasn’t what I learned—but how much I already sensed and ignored. Reading it felt like someone finally giving me permission to trust my instincts again. A must-read if you’re serious about reclaiming your mind.

[supersnail]

I’ve been using this to fall asleep every night this week!! I’m sure it’s a ton of work, but I’d love to see more 1+ hour videos <3

[nevermindidontknow]

Narrator's voice made me feel instantly calmer, very soft and soothing.

[SyberCerpent]

Into The Deep uploads a 4 hour video? HELL YES.

[riyaalicious]

this deserves so much more attention 🙏

[xthedetail]

I dont watch this to go to sleep. I watch it for the intrigue, love it all!

[theangryaustralian]

Never seen this channel ended up here round midnight just woken up after a rough couple of days...this exactly what i need in background how have i not seen this dude already

[MysteryAtlas]

I came here expecting a casual watch, but now I'm questioning everything. The atmosphere, the pacing, the mystery—absolutely mesmerizing. Who else paused just to process certain parts? 😳

[miguelgenovata]

the thing that makes mariana's trench even more scarier to think about is that in mt. everest, you can see all the dead bodies, succumbing to the cold environment whereas in the mariana's trench, you have no idea what kills things down there.

[DeenaMontanna]

Hearing, "grab a snack and get comfortable" made me realize. This is my home.

[YvonnePandora]

This is perfect for me today. My eyes are really tired so NOT having to WATCH is great! btw I'm a retired scuba diver so I can visualize much of what's being narrated.

[pipe_k]

Hey man, love the video, I'm listening while welding. I understand that producing a video this long is a lot of work and a lot of time, but I noticed you repeat yourself a little. It's not super distracting and I'm in no place to demand anything, but it would be great to improve that.
I hope you take it as constructive criticism, keep up the good work!

[natrob]

Thank you YouTube reccomendations for actually doing me a solid for once, your channel is just what I’ve been looking for thank you for making this!!

[TimeGateTV]

This video completely pulled me in—4 hours of mind-blowing deep sea mysteries I couldn’t stop watching! 🌊🦑 The ocean really is like an alien world right here on Earth. Every time I think we’ve discovered it all, something like this comes along and proves how little we actually know. From strange creatures to underwater anomalies, this had me hooked the whole time. Anyone else feel like the deep sea is even scarier and more mysterious than outer space? Seriously, props to the creators for such a captivating deep dive!

[qwertyx]

i was suppose to be sleeping now im deeply invested on this vid

[TheTimelessSecrets]

Fun fact: One of the most interesting things about the Yonaguni Monument is its possible alignment with the solstices, similar to ancient sites like Stonehenge. If true, this would mean whoever built it had advanced knowledge of astronomy—yet historians say no civilization in the area should have had that ability at the time.