Discovered in the early 2000s by a group of US scientists searching for dinosaur fossils in China's Qinghai province...
...the Baigong pipes consist of hundreds of pipe-like fossils found in three caves in Mount Baigong.
Mostly reddish-brown, many of the strange fossils stand upright in the ground, and range between 4 and 16 inches (10.16 to 40.64 cm) in diameter.
Now marketed as a tourist attraction by the local municipality, very little is known about the pipes and how they came to exist.
An analysis of the fossils found they're made up of 92% common metals and minerals, and 8% material of unknown origin...
...and atomic emission spectroscopy found the presence of organic plant matter and potentially rings, indicating the pipes could have been trees.
But "there is indeed something mysterious about these pipes..."
...remarked Zheng Jiandong, author of a Chinese earthquake administration report...
...who found some of them are highly radioactive, indicating they may have formed as the result of a unique and rare volcanic process.
During early 20th century excavations of the al-Ubaid archaeological site in southern Iraq...
...researchers uncovered some extremely odd figurines carved from stone that depict a mixture of humanoid and lizard-like shapes.
Roughly 7,000 years old, the artifacts date to the Ubaid period of prehistoric Mesopotamia that spanned from 5500 to 4000 BC
The Ubaid people lived in mud huts in large villages, farmed the land, and are believed to be early masters of water travel...
...but researchers have absolutely no idea what purpose the figurines served or why the pre-sumerian people had such an obsession with lizards.
The figures are either male or female, but most unusual is that all of the female humanoids are nursing tiny lizard-like babies...
...which historians say indicates the artifacts were probably not used in any sort of ritual or sacrifice.
Some hypothesize the Ubaid lizardmen were purely decorative...
...and others wonder whether they modelled the figures after some unknown hybrid animal that existed at the time.
In 1998, engineer John Williams, seeing what he thought was an electrical connector protruding from the ground, began digging...
uncovering a three-pronged plug, embedded in a small rock that has since been dubbed the Williams Enigmalith.
Fearing others would plunder the site, Williams has refused to divulge where he discovered the stone...
...but says it was an extremely rural area of North America.
According to Williams who had the rock examined by a geologist, the stone formed about 100,000 years ago...
...and the apparent electrical component was not glued or attached to the rock, but clearly already existed as the rock formed around it.
For Williams, this is evidence of the existence of advanced technology in ancient times, either of human or extraterrestrial origin...
...though skeptics claim the Enigmalith is a complicated hoax perpetrated by Williams, who's been trying to sell the stone for $500,000.
Roughly a hundred Roman dodecahedrons have been discovered across much of Western and Central Europe, dating back to 100 to 200 AD...
The mysterious hollow objects most often made of bronze and stone vary in size from 1,5 to 4 inches (3.81 to 10.16 cm)...
...and consist of 12 flat pentagonal faces, each with a hole exposing the hollow center, and knobs at the corners of the pentagons.
There exists no explanation in the historical record of how the Romans used the dodecahedrons...
...and the unusual objects baffle researchers to this day.
One common theory is that they were measuring devices used to calculate a projectile's trajectory on the battlefield...
...but the artifacts are not standardized and no proponent of this theory has ever described how it could accomplish the surveying task.
Others theorized they could have been pipe calibration gauges, ornate candlestick holders or even fortune-telling devices.
At this point however, none of the ideas proposed is supported by evidence, and the only thing that is known for sure about the Dodecahedra...
...is that they were highly prized by their owners, as most have been found stored among other treasures like gold and jewelry.
In 2011, amateur paleontologist Ron Fine discovered a giant, unusual fossil on a hillside in Northern Kentucky.
Naming the specimen Godzillus, because as Fine describes, it was...
"...like Godzilla, it's a primordial beast that found its way to the modern era."
Dating to roughly 450M years ago during the Paleozoic era...
when the region was covered by a shallow sea and some of the earliest life forms inhabited earth
The 150 lbs (68 kg) Godzillus, about the size of a single mattress is the largest fossil ever recovered from the area.
Other than its size and age, scientists know little else about the enigmatic fossil...
...even after a thorough examination at the University of Cincinnati.
"This one has us stumped" remarked geologist David Meyer, who said its "surface looks like scales, but this thing is not bony. It's not a fish."
Meyer is confident the fossil is "biological", but no evidence of others similar beastly organisms has ever been found.