Yes, the Thien Cung Grotto (Heavenly Cave) in Vietnam is lit up like a gaudy Vegas casino.
It’s also overly crowded and fairly kitschy, but underneath all that it’s still a beautiful old (like, formed 700,000 years ago old) limestone cavern.
The grotto is HUGE. It covers 3,000 square metres and has two floors, the second being about 20 metres above sea level.
While many limestone caves around the world are still actively dripping water that adds new deposits or fissures, Thien Cung Grotto is what’s considered a “dead cave”. What you see now is how it’s presumably going to remain for the next couple million years or so.
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While it’s an easy-to-reach attraction for tourists visiting Halong Bay, Thien Cung Grotto isn’t geared towards folks looking to enjoy stalactites and stalagmites in a more subdued manner.
I mean, it’s really more about hand puppets than intellectual discovery.
So if old rocks are your thing then you might want to consider the Carlsbad Caverns in New Mexico, which are more informative, well preserved, more naturally lit, and a heck of a lot less crowded.
Although, just as fair warning, they also like to “accidentally” lock visitors inside sometimes and turn out all the lights.
On second thought, maybe the Thien Cung Grotto isn’t so bad after all…

{ 36 comments… read them below or add one }
Wait, what do you mean they like to accidentally lock people in and turn the lights off? (I am so going to bring my own flashlight to that place…..)
Annie – FootTracker recently posted: My Mystery Meal @Matsumoto
I don’t know that they LIKE to, per se, but that’s what happened to us. The ranger didn’t know we were still in there so he turned all the lights out for the night!
Oooo, pretty colors. And some awesome rock formations!
Amanda recently posted: Tips for Visiting Yosemite National Park in One Day
The formations were incredible; I can’t believe what nature can do over a million years or so…
Lock visitors and turn off the lights? That does sound fun. LOL. I think we’ll wait for Mexico on this one..
Kieu ~ GQ trippin recently posted: 5 Sweet Eats in Hong Kong
Maybe not fun, but it sure does make a hell of a story, lol.
Someone has a wicked sense of humor! Wonder how they decide who gets locked in and I hope they don’t lock them in for too long. That would be scary.
InsideJourneys recently posted: #TPThursday: Crackling Pig Roast
No, it was an accident… thankfully. I would have been way more upset if it was a joke, that’s for sure!
Lol, I know what you mean. We went to Surprise Cave (Sung Sot) in Halong Bay last month, and it was super colorful and huge. Pathway for people complete with numerous penguin garbage bins and stop sign. Yes, inside!!! Green, purple, yellow lights, among other. And seems like they also make a fake pool near the entrance.
My last post happened to be on Halong Bay, check it out
Dina recently posted: Halong Bay Photostory
Ahhh, the penguin trash cans! Those things were actually pretty cute, but they seemed so out of place in Vietnam.
I’ll make sure to bring a flashlight when we visit the Carlsbad Caverns. We toured this cave and I was unimpressed. I guess I should have looked past the Vegas lights and saw it for what it truly is. How did you get such good photos? Mine were awful.
Christy recently posted: Sitting at a Crossroads
I used Kali for a tripod.
Actually, I don’t know how these turned out so crisp; most of them were blurrier than beer goggles, but somehow I got lucky with a few!
I don’t know why they need to hype up places like this, there is not need to compete with nature. I’ve seen the Ha Long caves and one in the Blue Mountains recently but it is kind of spoilt by all the hoo haa. My best cave experience was in France – the Gouffre du Padirac – stupendous nature!
Natasha von Geldern recently posted: Russia snapshot: Sergiev Posad
I agree that in this case, nature is the most impressive element and is just being obscured by all the bright lights. Thankfully it wasn’t completely obscured, though; the neatness of these caves still shines through.
Just as nature intended…
Caanan @ No Vacation Required recently posted: It’s a Wrap
Mother Nature LOVED psychedelic lights… right?
Amazing!!! Love the different colors. Looks like some part were well lit. Reall cool.
Ruth (Tanama Tales) recently posted: Eating Crazy Food in El Salvador
As gaudy as it was, they really did a solid job with the lighting. You can’t fault them for that!
I won’t lie – I visited here while in Vietnam – and the cave just didn’t do it for me. With my inadequate hand-puppet skills, I found myself longing to be outside with the karst rocks. I play favourites with rock types. And I went into a cave with only a head-light on and we just kept going – I could feel the weight of the cave around me and my heart started racing and I had to get out. I couldn’t stand NOT being able to see natural sunlight and knowing I was deep in the ground.
Did you feel that being locked in?
Chrystal McKay recently posted: Photo Diary: Inspiring Colours of the Jardin Majorelle
Yeah, caves are pretty freaky once you get past a certain point. Thankfully we didn’t feel claustrophobic when the lights were turned out on us in NM, but we were in the complete dark with no clue as to what happened!
I remember going there, it was such an odd experience to see it turned into an amusement park-like cave – not what I expected at all.
Ayngelina recently posted: Food Friday: Where to eat in Hana?
It really did look like an amusement park; throw in some carnival music and it would have been complete!
These caves remind of the one I visited in Slovenia. We have caves like this here in California as well. However, I don’t think they turn out the lights and lock the doors on those though
Jeremy Branham recently posted: 5 tips on how to make a video while traveling
That’d be a bad publicity stunt if they did.
Thanks for the New Mexico warning! I have relatives in that state, and I’m sure that had I stayed longer, we would have gotten there. A colorful place is my kind of place, though it does look bizarre.
Ayelet – All Colores recently posted: On the Way to Jerusalem’s Ice Festival: A Slight Error in Direction
Don’t completely avoid the Carlsbad Caverns – just bring a flashlight!!
This looks like a lot of fun. Yes, kitschy but entertaining. May have to try it when I get to Asia in the fall.
Jonathan Look, Jr. recently posted: Street Food | Chicatanas
As long as you’re not expecting to see limestone caves in their “natural” environment, then I agree that this is pretty neat to see.
WOW those caves look amazing and those colorful lights are helping to highlight the structure of the caves.
Armands recently posted: Romancing the Rails – Best Train Journeys in Europe’s Most Popular Countries
I like your positive spin on it, Armands!
They turn the lights out on you? Eek! I’m good skipping this attraction…
Camels & Chocolate recently posted: Photo Friday: Bardstown, Kentucky
Not all the time! Just, y’know, once in a while.
It looks pretty cool, but the crowds and the potential lights being turned out doesn’t really sound appealing. I’m already not a big fan of caves. Definitely sounds like an interesting experience though!
Ali recently posted: Bad Beds Around the World
I don’t know if they turn out the lights at the Thien Cung Grotto, thankfully. It’s a huge cavern to escape from!
How weird that they light up everything! That would make me less interested. But I’d probably still go
Scott – Quirky Travel Guy recently posted: Elvis Presley, Johnny Cash and more at the Country Music Hall of Fame
That’s the spirit!