Hypogeum of Hal-Saflieni
Whoever built this three-level underground complex in Malta around 4000 BC and used it through 2500 BC is not only a mystery, but had skills that remain nearly as perplexing. The acoustics of the Oracle Room are so powerful that male voices (yes, usually just male voices) can reverberate throughout most of the entire complex. We’re still not sure how this was achieved, especially considering it would have been carved with basic tools like antlers and obsidian. In this rare case, the purpose is potentially better understood than the method of construction: It was likely a necropolis. Seven thousand bodies were discovered within when the Hypogeum when it was unearthed in the early 1900s.
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Likely established as early as 100 BC, this Mesoamerican city’s exact origins are unknown. What we do know is that at its height, the city was home to 100,000 people from a number of Mesoamerican cultures, including the Otomi, Zapotec, Mixtec, Maya, and Nahua, all of whom contributed to what made Teotihuacán one of the first great cities in the western hemisphere. Even the Aztecs, who arrived long after the city had been abandoned, gave the site its name (which roughly translates as “City of the Gods”) as it’s known today. It’s clear that multiple cultures through history played a hand in the complicated construction of this once-epic city, but the city’s initial architects remain a mystery, causing many to wonder what valuable knowledge may have been lost to time.
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The creation of this sixth-century complex alone causes researches to scratch their heads. Stone slabs as large as 131 metric tons were hauled up a steep hill, then locked together like a jigsaw puzzle so precise that the Inca, who believed the site to be the place where the world was created, thought it was accomplished by gods. It’s likely that the Tiwanaku assembled this impossibly heavy and perfectly aligned puzzle. Their skills not only continue to baffle modern researchers but the Inca, who emulated their mortarless jigsaw-puzzle style of engineering, though they couldn’t match the Tiwanaku’s advanced skills when it came to mass production.
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Two thousand miles from its nearest neighbors, Easter Island remains the most remote inhabited island on Earth. Making it all the more difficult to comprehend how its famous monumental heads (and oft-overlooked subterranean bodies) were sourced, transported, and strategically placed around the small island. Not only aren’t we sure how, but we don’t really know why, or even who or what they represent. The 14-ton figures number around 900, and the vast majority of the Polynesian colonizers who created and arranged them mysteriously abandoned the quarries where the statues were made, so we aren’t likely to find answers anytime soon.
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Possibly dating back as far as 500 BC, the Nazca lines are enormous geoglyphs (“drawings” made on the ground) that depict animals, humans, and precise geometric shapes, some extending up to 1,200 feet long. Though they were first reported by a Spanish conquistador, who mistook the lines a trail markings in the 1500s, it wasn’t until the 1920s when they reported by Peruvian pilots and studied by archaeologist Toribio Mejía Xesspe that the lines sparked peoples’ curiosity, leaving many to wonder how they were made, why they were made, considering these massive artworks can only be seen in full from the sky. Though their purpose is still debated by scholars (a common theory that they were meant to connect sacred sites, while others argue they indicated water sources, or that they served as astrological maps), it’s been determined that they can be seen without taking flight by standing on certain hills. Still, even though most of the mystery surrounding the Nazca lines has been solved, the precision and size of these artistic spectacles continue to draw admirers year after year.
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Temple of Jupiter at Baalbek
The Temple of Jupiter at Baalbek is a Roman temple, but it’s what was on this site before the temple that catches the attention of the most curious. A previous temple was built here, likely by the Phoenicians, and the incredibly massive stones in the foundation are baffling to archaeologists. The blocks are the largest ever known to world history and weigh from 800 to 1,500 tons each, depending on whose calculated estimates you trust. How and why these unnecessarily gigantic and cumbersome blocks were cut and used is still unknown, and why this construction was so unique is equally mysterious. Most baffling of all is that there are no written, or even oral, records of why the Romans or Phoenicians built this singular site, so unlike any other from antiquity–though they left prolific, written explanations of just about every other aspect of their cultures.
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Ah, that relatively small circle of enormous stone slabs only about 13 feet high but topping the scales at around 25 tons each. We all know it for its astronomical accuracy, but many of Stonehenge’s characteristics make it unique and mysterious, even among other stone circle “calendars” of its era. The site dates back about 5,000 years and has been built and rebuilt multiple times over the millennia, but the truth is we have no solid proof of how it was erected in its current form or what the site was ever actually used for, though plenty of bones have been found below it. Theories abound as to its origin and purpose, but because the civilization that built it left no records, we’ll probably never really know for sure.
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The walls of Sacsayhuamán may not be the most famous landmark in Peru (Machu Picchu is the most Instagrammed spot in all of South America) but they sure do captivate. The site dates back to about 1100 BC, with some early sections believed to have been built by the Killike, but the Inca-built walls of the 13th century boggle most minds. They’re massive, comprising 6,000 cubic meters of rocks reaching up to 200 tons each, and mysteriously arranged in a zig-zag pattern for purposes unknown. Still, it’s the precision of their construction that inspires the most awe. Aside from the sheer scale of the rocks, they’re assembled without any mortar and they’re shaped and fit together so exactly that no space at all is detectable between them. The Incas were masters of this mortarless style of masonry and implemented it throughout their empire.
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