10 Monumental Ancient Achievements That Are Still Unsolved By Modern Science

The construction of Great Pyramid of Giza in Egypt has long perplexed archaeologoists (CC- Sam valadi)
Image: Sam valadi
The methods used to construct the Great Pyramid of Giza in Egypt have long remained a mystery to archaeologists.

Thanks to the incredible accomplishments of modern science, archaeology and astronomy, we now know much – and are constantly learning more – about the amazing planet we inhabit and the galaxy in which it is found. Nonetheless, though the groundbreaking work of the likes of Charles Darwin and Isaac Newton has helped us to better understand ourselves and our world, scientific inquiry has not proven infallible, and there are still many achievements from the past that remain unsolved – not least, regarding how and why they came into being. The following ten ancient sites and accomplishments, for example, have left scientists and archaeologists scratching their heads in amazement to this day.

An electrical storm near the mysterious Stonehenge close to the town of Salisbury, England (CC-Kate Williams)
Image: Kate Williams
In 1986 Stonehenge was designated a World Heritage Site, but still no one knows for sure how it was created.

10. Stonehenge

Nestled on an open plain to the north of Salisbury in England, Stonehenge is an awe-inspiring monument that remains shrouded in mystery even today. The site’s “Stone Circle” centerpiece – comprised of sarsen stones averaging 25 tons apiece and smaller bluestones each tipping the scales at as much as four tons – has dumbfounded archaeologists for centuries. And debate continues to rage about how the preposterously heavy stones were shifted to the site, how they were positioned to form the monument and, crucially, why the construction was even made in the first instance.

Stonehenge is one of the wonders of the world and the best-known prehistoric monument in Europe (CC-Nelson L)
Image: Nelson L.
Archaeologists are still divided about how the incredibly heavy stones made it to Salisbury Plain.

Indeed, exceedingly few pointers were left for archaeologists about the creation of the Neolithic-period wonder, whose building, it is estimated, began in around 3,100 B.C. Theories on how the stones – native to Wales – were moved to Salisbury Plain range from the idea that glacial movement pushed them closer to the site to the notions that they were transported across water by raft or that the Neolithic people simply carried them there. As to why the monument was even created, well, it’s now thought that it’s likely to have been in order to forecast lunar eclipses – although naturally this is only a hypothesis. What is undisputed, though, is that Stonehenge is remarkable for its era.


The Great Pyramid of Giza is located west and south of modern Cairo, in the vast desert imagined by the ancient Egyptians (CC- see document)
Image: Barcex
The Great Pyramid of Giza stands tall in the immense desert to the southwest of modern Cairo.

9. Great Pyramid of Giza

One of the Seven Wonders of the Ancient World, the Great Pyramid of Giza is an archaeological marvel of the highest order. Traceable back to around 2580 to 2560 B.C., it is the biggest and most longstanding of the three pyramids in the vast Egyptian desert to the southwest of the country’s capital, Cairo, and remains a much investigated and visited site. However, knowledge about how it was constructed is still hazy thousands of years since its creation.

Great Pyramid of Giza
Image: Nina
The archaeological marvel also goes by the name of the Pyramid of Khufu or Pyramid of Cheops.


With minimal literature in existence pertaining to Egyptian building methods, archaeologists have been trying to figure out how the heavy stone blocks used for the construction of the tomb of King Khufu were excavated, dressed and moved to the desert. Furthermore, there is no concrete knowledge about how the structure was positioned there so magnificently, lining up with the stars with considerable exactitude. So spectacular is the Great Pyramid, moreover, that there are still conspiracy theorists who claim that it and its surrounding smaller pyramids are in fact the creations of aliens.

Sacsayhuamán is a walled complex near the old city of Cusco(CC-Tyler Bell)
Image: Tyler Bell
The incredible walled site of Sacsayhuamán in Peru sits close to the ancient city of Cusco.

8. Sacsayhuamán

Sitting at a lofty altitude of 12,000 feet in Peru, the spectacular walled citadel of Sacsayhuamán has been amazing archaeologists and scientists alike for many years. There has been much bafflement at how the giant walls of the Inca-developed stronghold were shaped and slotted together so successfully that not even a blade of grass is able to penetrate its joins.


Sacsayhuaman, where the Incas’ construction of tightly placed stones created an incredible series of walls(CC-Esoltas)
Image: Esoltas
Archaeologists are in awe of the Inca people’s construction of Sacsayhuamán.


The whole complex – from which the ancient Inca city of Cusco is visible below – consists of three walls of hefty limestone boulders found at different heights but running alongside one another. It has proved dumbfounding to many observers how the boulders – which individually weigh as much as around 154 tons – were transported to such an elevated altitude and how the meandering walls were sculpted and joined so exactly as to not require mortar. The overall effect: the sense of a truly mind-boggling feat of strength and stone masonry.

In the ruins of the Jupiter Baal Temple lie three hewn stones known together as the trilithon(CC-Jerzy Strzelecki)
Image: Jerzy Strzelecki
The awe-inspiring Trilithon lies in the ruins of the Jupiter Baal Temple.

7. Trilithon at Baalbek

It was during the Roman era that the Lebanese city of Baalbek’s most famous landmark was built: the Jupiter Baal Temple, which contains the renowned Trilithon. The Trilithon consists of three some 750-ton-apiece-plus stones carefully cleaved into shape. Archaeologists, meanwhile, remain mystified as to how the humongous blocks were transported many miles from their original quarry and then lifted carefully into place at the site.


The Stone of the Pregnant Woman weighs an estimated 1,200 tons (CC- Ralph Ellis)
Image: Ralph Ellis
Weighing in at around 1,200 tons, the nearby “Stone of the Pregnant Woman” is even heavier than those of the Trilithon.


One theory suggested by French archaeologist Jean-Pierre Adam as to how the mammoth stones reached the site is that they were transported by means of rollers alongside primitive machines with a pulley system and capstans. This method would nevertheless have required considerable manpower: Adam puts forward the idea that an incredible 512 workers may have been needed to shift a 557-ton stone in this way. It’s worth noting, though, that a stone of this size is still around 200 tons lighter than those of the Trilithon. Meanwhile, beside the Trilithon lies an even larger block, nicknamed the “Stone of the Pregnant Woman,” which weighs in at roughly the same as three jumbo jets. This monolith was mysteriously left pointing upward out of the ground; even the Romans, it seems, had their limits.

Easter Island was discovered by a Dutch sailor who found the island on Easter Sunday in 1822(CC-Nicolas de Camaret)
Image: Nicolas de Camaret
Easter Island earned its name after being found by a Dutch sailor on the day of Christian celebration in 1722.

6. Easter Island statues

Hidden away in the South Pacific Ocean off the Chilean coast, Easter Island is a place shrouded in mystery and wonder. The 64-square-mile land mass was found by a Dutch seafarer on Easter Sunday in 1722 and is renowned for the numerous and enigmatic moais – wonderfully carved statues that in some instances are as heavy as 50 tons – littering the scene.


Over 100 large carved stone heads exist all over the island (CC-TravelingOtter)
Image: TravelingOtter
Remarkably little is known about the community that first lived on Easter Island or the giant statues that dwell there.


No one knows for sure how these large, heavy figures – which number more than 100 and stretch to over 32 feet tall – were constructed and transported across the island. One theory is that trees were cut and used as rollers to shift them, which perhaps accounts for the relative scarcity of foliage found on the island today. Furthermore, there is great mystery surrounding the disappearance of the inhabitants who made the statues from around 1250 until 1500 A.D. Among the suggestions concerning their ultimate fate are the idea that they became extinct thanks to disease and the notion that the community eventually perished due to overwhelmingly plundering the island’s natural reserves.

The Gate of the Sun was rediscovered by European explorers in the mid-19th century lying horizontally with a large crackthrough it (CC- Mhwater)
Image: Mhwater
Europeans unearthed the Gate of the Sun in the mid-1800s.

5. The Gate of the Sun and ancient ruins of Tiwanaku

The architectural achievements of the ancient peoples who created the pre-Columbian settlements of Tiwanaku in western Bolivia have long confounded those who have studied them. The timeworn ruins that linger in the area – including the sizable temple compound of Puma Punku – seem to represent the toil of constructional geniuses. And what’s still under question is how the site’s large stone blocks – some weighing in excess of 100 tons – were hauled over 50 miles from where they were quarried in a period before horses were utilized.


The Gate of the Sun in Bolivia is approximately 3 metres tall and carved on a single block of stone (CC-Dennis Jarvis)
Image: Dennis Jarvis
The Gate was found lying on the ground with a sizable crack running through it.


Furthermore, both how the stones were fashioned – they bear no chisel indentations – and their innovative three-dimensional interlocking have amazed observers. Perhaps the crowning architectural achievement on the site, though, is the Gate of the Sun – a nearly ten-foot-high megalith arch with mysterious carvings cut out of just one slab of stone. When this was unearthed in the mid-1800s, it was found lying parallel to the ground and with a substantial fissure in its midst. Moreover, the meaning of its inscriptions have created much debate, although they are purported by some to have an astronomical significance.

The geoglyphs, known as Nazca Lines, were spotted from the air in 1939 (CC-Christian Haugen)
Image: Christian Haugen
The Nazca geoglyphs were first seen by an astonished pilot flying over the Peruvian area back in 1939.

4. Nazca Lines

The widespread fascination with the mysterious Nazca Lines began in earnest after their discovery in 1939 by a pilot marshaling an airplane over the highlands of Peru. Ever since, there has been considerable questioning into the origins of the intricately detailed geoglyphs, some of which depict animals and human-like figures.


Nazca lines dogImage: Colegota
UNESCO named the mysterious Nazca Lines area a World Heritage Site in 1994.


The discovery of the lines – themselves attributed by some to the ancient Nazca people of Peru – has given rise to many queries. First, given that they can only properly be viewed from high up in the sky, how were they so artistically inscribed in an era way before the invention of human aviation? And why were they even created in the first place? Perhaps, however, John Kosok hit upon a reasonable suggestion as to why they were made. In 1941, a mere 24 hours after the winter solstice, the American academic stood at the base of one such line only to find himself directly lined up with the sun – suggesting that the Nazca people of around 400 to 650 A.D. knew their astronomy.

Ollantaytambo was a highly effective fortress, it also served as a temple(CC-Wolfgangbeyer)
Image: Wolfgangbeyer
Ollantaytambo’s formidable fortress is also thought to have served as an Inca place of worship.

3. Ollantaytambo fortress

As good an example as any of the Inca people’s revolutionary feats in architecture and engineering, the fortress in the ancient city of Ollantaytambo in Peru is truly something special. However, the construction of the city – not to mention the fortress itself – has elicited many questions from those eager to figure out how the Inca civilization could have extracted and transported such large rocks from the mountainside. Scholarly inquiry has subsequently led to a suggestion that the stones were ferried across both a river and a plain before being dragged up its own mountain.


Image: Hakan Svensson
Boasting a strategically important position high up in the Sacred Valley, Ollantaytambo was a crucial part of the Inca Empire.


Another somewhat mysterious feature at the site is the famed “Wall of the Six Monoliths,” a huge, six-part edifice whose assembly was jettisoned by the Incas for reasons unexplained. The fortress, meanwhile, was initially conceived as a temple, although it is also rumored to have once been a site of astronomical importance.

Since the 1930s, hundreds of stone balls have been documented in the Diqius Delta of Costa Rica (CC-Rodtico21)
Image: Rodtico21
Several of the enigmatic spheres of Costa Rica were happened upon in the 1930s by United Fruit Company employees.

2. Stone spheres of Costa Rica

It’s fair to say that 1930s United Fruit Company employees blazing a trail through the Costa Rican jungle got more than they bargained for. Those workers – busy making room in the foliage for new banana plantations – were likely scratching their heads when they stumbled upon a sizable number of stone spheres of a variety of different sizes and weights spread across the jungle floor. There had been hearsay from adventurers about the objects sometime before then, but now their enigmatic existence was common knowledge.


So who sculpted these mysterious spheres – ranging in size from that of a baseball to a small automobile – and why? Well, given that no records or documentation on them exist, and that it’s likely that many of them have been moved, answers to these questions have proved elusive for archaeologists. The University of Kansas’ John Hoopes, though, has suggested that they may have had astronomical or directional significance – this on the basis that many were arranged in straight and bowed configurations. Even the era in which they were created remains the subject of debate; Hoopes has said that the spheres could have come into existence at any point within a 1,800-year historical span.


A group of divers explore the Yonaguni ruins (CC-Vincent Lou)
Image: Vincent Lou
Found just off the coast of a small Japanese island, the enormous underwater rock structures of the Yonaguni Monument are shrouded in mystery.

1. Yonaguni Monument

A mysterious set of submerged rock structures found by an inquisitive scuba diver back in 1986, the so-called Yonaguni Monument has since prompted many a theory as to its original purpose. It has even been posited that these ruins are in fact the remains of an ancient lost city drowned beneath the waves approximately two millennia ago.


A scuba diver explores the mysterious Yonaguni Ruins in Japan (CC-jpatokal)
Image: Jpatokal
It has been suggested that the Monument may once have been part of an ancient city.


Perhaps the chief proponent of this view, moreover, is Japanese marine geologist Masaaki Kimura, who has suggested that the city was forced under the sea as the result of an earthquake. Others who have dived there, however, are more skeptical. American geologist Robert Schoch, for example, advances the notion that erosion and tectonic activity have naturally fragmented the rock to create the illusion that the array of blocks and structures was carefully man made. It seems as though the jury is still out on this fascinating underwater find.