Human history is filled to the brim with unsolved mysteries like lost cities, ancient devices, unidentified fossils, and other ridiculous finds that have baffled researchers for decades or even centuries. But, thanks to modern science and technology can finally slap a "solved" stamp over some of those ancient curiosities.

Here are 10 ancient scientific mysteries that have finally been solved.

The Lost City of Ubar

The legendary city of Ubar was said to have vanished somewhere in the deserts of Oman. For hundreds of years, this mythical city was treated as nothing more than a fairy tale. But then modern remote sensing provided researchers with a significant clue.

Thanks to satellite imaging, researchers were able to trace ancient caravan routes across the desert. The processed data clearly indicated that these routes converged near Shisr in Oman, where archaeologists later discovered a fortress-like site associated with the incense trade.

Roman Concrete

Roman buildings, roads, aqueducts, and more have survived for nearly 2,000 years. So what's the secret ingredient of the ancient Roman concrete?

A 2023 MIT study has provided new insights into this mystery.

Researchers discovered that the Romans used quicklime during the process called "hot mixing," creating tiny lime clasts inside the concrete, which may have helped to "self-heal" the small cracks over time.

In other words, whenever Roman concrete cracked, it began to heal itself and became even stronger.

The Tully Monster

The Tully Monster is one of the weirdest fossils ever found. Discovered in Mazon Creek, Illinois, it had a soft body, stalked eyes, and a weirdly long snout-like appendage. Scientists could not agree on what it was until 2016, when someone argued that it was a vertebrate related to lampreys.

However, when a recent study used experimental 3D scanning technology, the researchers found details that cast doubt on the whole "vertebrate" assumption and suggested the fossilized creature may have been an invertebrate after all.

The Ancient Canaanite Comb

A small but quite ancient comb found at Lachish in Israel had a barely legible inscription that took years to notice and decode.

When researchers finally read it, they were surprised because the message was not royal, religious, or poetic.

It was about lice. Yes, the 3,700-year-old scribbles are believed to say something like, "May this tusk root out the lice of the hair and the beard." That makes it one of the oldest known full sentences written in an early alphabetic script.

The Ichthyosaur Confusion

Ichthyosaurs were basically a mix of a fish and a lizard, and they looked a bit like dolphins. Their fossils were discovered and named in the 19th century, but they were really rare and incomplete, which inevitably caused some confusion when people found new fossils.

As time passed, researchers began to realize that the fossilized remains of some of those species were actually bits and pieces of previously discovered ones.

The mystery was less about an unidentified creature and more about the confusion surrounding early fossil classification.

The "Impossible" Egyptian Statue

An Egyptian statue in the National Museums Scotland collection seemed to break the rules of conduct between the Pharaoh and the rest of the people. It is a statue of a small pharaoh sitting in the lap of a kneeling non-royal figure. In ancient Egyptian art, it was almost impossible to find a Pharaoh in a diminutive pose like this one.

Curator Margaret Maitland traced the statue's background to Deir el-Medina, the village of skilled workers who built royal tombs near the Valley of the Kings. For their masterful work and uncanny craftsmanship, these workers got some extra privileges, including more freedom to depict their rulers.

The Mayan Calendar

The Mayans were undeniably brilliant in astronomy, but their 819-day calendar baffled modern scientists. Scholars assumed the calendar was linked to planetary movements in some way, but the numbers did not make sense.

The breakthrough occurred when researchers expanded their focus beyond a single 819-day cycle. When they extrapolated the system across 20 cycles (16,380 days), they noticed that the movements of visible planets such as Mercury, Venus, Mars, Jupiter, and Saturn fit much better.

So in the end, the Mayans were thinking on a much bigger astronomical scale than the rest of the world.

The Antikythera Mechanism

You may have never heard of the Antikythera Mechanism, but you've definitely seen it. In 1901, a shipwreck revealed this peculiar device, revolutionizing people's perceptions of ancient technology.

Modern scanning and 3D modeling have helped researchers better understand how it worked. They reconstructed part of the device's display, suggesting it may have shown the movements of the celestial bodies, including the sun, moon, five visible planets, and even potential eclipses.

Ancient Roman Perfume

In Carmona, Spain, researchers stumbled upon a sealed perfume bottle that had survived for around 2,000 years. Because the container was still intact, scientists were able to analyze what was inside.

The results of the chemical analysis were quite surprising. It appeared that the mixture contained some kind of oil and extract of patchouli, which is still commonly used in modern perfumes.

Hidden Spaces in the Great Pyramid

The Great Pyramid of Khufu has been studied for centuries, and yet it still holds many secrets. Using cosmic-ray muon imaging, scientists detected hidden voids inside the pyramid without drilling into it or damaging the structure.

In 2017, researchers found a hidden chamber above the Grand Gallery. Then, in 2023, a series of corridors and walkways were discovered, leaving archaeologists dumbfounded.