I don’t say this very often, but this page is SO COOL. I’m talking about a Reddit page called What Is This Thing, and it’s exactly what it sounds like.

People post photos of things that they’ve found or seen and they never have a clue what the objects are.

Then, Reddit users figure it out for them and we all learn something!

Let’s take a look at some really interesting examples.

1. A house for trolls?

“It’s a fridge, or a old time cold room. Basically a room covered with dirt for insulation.”

Saw this in a forest in germany from whatisthisthing

2. DO NOT REMOVE.

“Aztec calendar. Funny thing, I remember a bunch of these a while ago being smuggled over the border and they were made of meth.”

My grandfather told us to NOT remove this when renovating. from whatisthisthing

3. What the hell…?

“It’s potato art… And I’m not even kidding… The artist is unknown (some say by an artist called NoNose), if you look for ‘London bus stop potato art’ you can find many more articles written about it.”

What are these things I keep seeing on nearly all the London bus stops in my area? from whatisthisthing

4. Little creatures.

“Stonefly larvae. Good sign for the water quality.”

Found in deep creek MD from whatisthisthing

5. Coming out of the ceiling.

“Those are the studs from your walls — redistributed by your termites.”

Growing from the basement ceiling at a very rapid rate. It is also leaving on the table below it, grayish particles. from whatisthisthing

6. Can someone please identify this?

“Jar opener.”

On the underside of our cabinet in the house we recently bought, built in the 70s. Plastic with metal teeth on one side, very dull. Each side is ~4 inches long. from whatisthisthing

7. Well, did he win?

“Hoof pick for cleaning horses hooves.”

Found this in my house. I bet my wife it has something to do with a tie. Do I win? from whatisthisthing

8. Watch your knees.

“Skateboard prevention device. Keeps em from grinding on edges.”

What are these circular metal things on these stairs? I just hit my knee and goddamn did it hurt. from whatisthisthing

9. Mysterious numbers.

“Magic square. It’s a popular sort of decoration to put outside math departments.”

Plaque with numbers inscribed on it. Found on the sidewalk outside a building at my university. from whatisthisthing

10. That old, rusty thing.

“It is an underwater mine.”

Saw this rusty thing on my walk in a forest. The forest belong to a estate (Wedellsborg, Vestfyn, Denmark. from whatisthisthing

11. Are you in a futuristic film?

“Those look like midge eggs, an aquatic fly.”

Found in the wood in a creek. It was under a piece of wood. from whatisthisthing

12. What could this be…?

“Alvernia Studios is a film studio located near Kraków, Poland, 18 km (10 miles) from the Kraków-Balice Airport, with additional offices in Mumbai and Warsaw.”

This sci-fi looking place in Poland, somewhere by Krakow from whatisthisthing

I’ll say it one more time: THOSE ARE SO COOL!

Now we want to hear from the readers out there! Have you ever used this Reddit page to find out what something was? Or maybe you helped someone else figure out what a mystery object was?

Please tell us your stories in the comments!