Book summary “Underworld”: summary

Introduction

Standard history teaches that human civilization began in Mesopotamia and Egypt a few thousand years ago. You look at maps of the ancient world and assume coastlines have remained largely stable throughout human existence. Yet orthodox archaeology ignores vast continental shelves that were dry land during the last Ice Age.

Graham Hancock argues in Underworld that rising seas at the end of the Pleistocene submerged advanced maritime civilizations whose ruins still rest on continental shelves. You explore how global flood myths, ancient maps, and underwater megalithic structures point to a lost chapter of human history.

The book takes you on a global diving expedition across submerged sites, ancient flood zones, and coastal ruins.

• What secrets lie hidden beneath the shallow continental shelves of the world?
• How do ancient flood myths align with the mechanics of the Ice Age meltdown?
• What do submerged ruins in India, Japan, and the Mediterranean reveal about lost human capabilities?

1. Diving into the Underworld

Acquiring diving skills enables you to investigate mysterious submerged structures around the world that challenge established archaeological timelines.

Diving Methodology

Graham Hancock and his wife Santha completed their PADI Open-Water courses in Catalina Island, learning to manage neoprene wetsuits, buoyancy control devices, compressed air tanks, regulators, and wrist computers.

In November 1996, Hancock and his wife trained in the cold waters off Catalina Island, using heavy lead weights and multi-hose regulators to prepare for deep dives.

You need to prepare your gear carefully before entering the water. Follow these steps for proper equipment setup:

• Wear short rubber boots tucked inside wetsuit ankle-cuffs.
• Strap fins over boots to prevent clumsy movement.
• Attach a stainless-steel knife to the calf for cutting away netting hazards.
• Fasten a weight belt around the waist to offset body and suit buoyancy.
• Wear an inflatable Buoyancy Control Device with a strapped scuba tank.
• Breathe through a two-stage regulator system connected to the compressed air tank.
• Wear a glass-fronted mask, a wrist computer, and protective gloves.

Tank sizes include 10, 12, and 15 litre capacities, with a mid-sized tank weighing 15 kilos. Inexperienced divers initially use 12 to 14 kilos of lead weight.

Submerged Ruins of Japan and India

Anomalous terraced structures off the Japanese island of Yonaguni suggest the existence of monumental architecture carved before the end of the Ice Age. The structures exhibit flat planes, right-angles, megalithic walls, and staircases hewn directly out of solid bedrock when the site was above water.

Ken Shindo approached Graham Hancock after a lecture in Japan in 1996, showing underwater photographs of terraced structures off Yonaguni at depths of up to 30 metres. These formations feature parallel blocks weighing 30 tonnes and date to an approximate inundation of 10,000 years ago.

Submerged stone circles and megalithic alignments off the Kerama islands point to prehistoric activity in areas now affected by severe tidal currents. Local divers identified concentric rings of upright megaliths and rectilinear formations near Aka Island at depths reaching 30 metres.

At Aka Island in the Kerama group, divers explored Centre Circle, which features concentric rings of upright megaliths more than 3 metres tall hewn from bedrock. The site sits 40 kilometres west of Okinawa and includes formations spanning 20 metres in diameter alongside a larger 150-metre stone circle.

A mysterious man-made U-shaped stone structure lies submerged in the Bay of Bengal, challenging orthodox historical timelines. Glaciologist Glenn Milne's computer models indicate that the site was submerged around 11,000 years before the present due to post-glacial sea-level rise.

In March 1991, National Institute of Oceanography divers including T. C. S. Rao investigated anomalies off the Tranquebar-Poompuhur coast, eventually locating the horseshoe-shaped stone formation at 23 metres depth 5 kilometres off the south-east coast of India with an 85-metre peripheral length.

2. Floods and Sumerian Origins

Ancient flood legends and geological data from the Persian Gulf point to antediluvian civilizations beneath the sea.

The Sumerian Flood

The oldest surviving written version of the global flood myth is preserved on a broken Sumerian clay tablet found in Nippur. The lower third of a six-column tablet describes the creation of life, the lowering of kingship from heaven, and the foundation of five antediluvian cities before a universal flood destroys humanity.

Excavations at Nippur, located 200 kilometres south of Baghdad, uncovered the rare baked clay tablet detailing the story of the flood hero Zisudra. Thirty-seven lines describe missing sections at the beginning and middle of the Sumerian tablet. Seven days and seven nights mark the duration of the flood while Zisudra's boat is tossed on the waters.

Sir Leonard Woolley excavated a thick layer of water-laid silt at Ur, which he interpreted as physical proof of the biblical and Sumerian flood. Woolley found a three-metre layer of clean clay void of habitation evidence during excavations at Ur between 1922 and 1929, though later researchers suggested it was a marine transgression rather than a river flood.

Sir Leonard Woolley dug through habitation layers at the Sumerian city of Ur and reached a layer of silt almost 3 metres deep. The habitation layers below the silt layer at Ur date back to 3200 BC.

Geology of the Persian Gulf

Geological research indicates that the entire floor of the Persian Gulf was dry land during the Last Glacial Maximum and was progressively flooded over thousands of years. Kurt Lambeck's simulation of palaeo-shorelines shows that the Persian Gulf was dry land between 18,000 and 14,000 years ago, after which marine incursions gradually submerged the valley.

Kurt Lambeck mapped paleo-shorelines showing that the Strait of Hormuz opened as a narrow waterway around 14,000 years before present. Glacio-isostatic effects and the Flandrian transgression occurring between 6000 and 5500 years ago flooded the coastal plains of Sumer.

Graham Hancock hypothesizes that the true origins of Sumerian civilization and its antediluvian cities lie veiled beneath the waters of the Persian Gulf. Because the Persian Gulf floor was entirely exposed until 14,000 years ago and featured a fertile river valley with ideal climate conditions, permanent settlements and early urban centers likely evolved there before being submerged by post-glacial sea-level rise.

The Great Pearl Bank between Dubai and Qatar remained above water until shortly after 8000 years ago, coinciding with the establishment of Eridu. The Eastern Basin, Western Basin, and Central Basin formed part of a well-watered landscape where the Indian monsoon penetrated south-west Asia and the Gulf between 12,000 to 9000 years ago, operating through a key period of Ice Age meltdown and ocean turbulence lasting from 14,000 to 7000 years ago.

3. Mechanics of the Ice Age Meltdown

As continental ice-caps melted between 17,000 and 7,000 years ago, global sea levels rose by 120 metres. You find that this marine transgression swallowed approximately 25 million square kilometres of desirable coastal and low-lying land.

Massive post-glacial superfloods and crustal rebalancing rapidly submerged vast coastal lowlands across the globe.

Sahul, or Greater Australia, extended from the Equator to 44 degrees S and lost more than three million square kilometres during the marine transgression. Nearly five percent of the earth's surface was submerged since the end of the Ice Age.

Glacial Mechanics

Through the process of isostacy, ice loads thousands of billions of tonnes onto landmasses, depressing the crust into deep basins. When the ice melts, the land slowly rebounds, while surrounding peripheral zones subside.

Ice-caps over North America and northern Europe reached a thickness of 2 to 4 kilometres. This massive weight caused a depression of the earth's crust by 700 to 800 metres.

The Fennoscandian ice-sheet depressed the northern European continental crust, creating a forebulge that elevated southern England and the Isle of Wight, which are now subsiding as the forebulge collapses.

Cataclysmic Superfloods

Geological data indicates that nearly half of the total meltwater release was concentrated into three short episodes occurring approximately 15,000-14,000 years ago, 12,000-11,000 years ago, and 8,000-7,000 years ago.

Cesare Emiliani found a 2.4 per cent isotopic anomaly in deep-sea cores from the Gulf of Mexico, indicating major meltwater flooding centered around 11,600 years ago.

Sub-glacial lakes formed as geothermal heat melted the bottom of ice sheets. When the ice barriers failed, massive torrents of water and debris rushed into the oceans, causing sudden jumps in sea level.

The collapse of an ice dam holding back Lake Missoula in the American Northwest 13,500 years ago released about 2,000 cubic kilometres of meltwater, carving the Channelled Scabland.

4. Ancient India and Vedic Traditions

Vedic texts and archaeological sites in India preserve maritime traditions and memories of catastrophic glacial floods.

Vedic Oral Tradition

Brahmins maintained the sacred Vedas as sruti through standardized learning processes and peer pressure. This practice ensured that even distant regions recited the exact same sounds and words without writing them down for centuries.

The Vedic hymns were preserved across millennia with extraordinary accuracy exclusively through oral recitation and strict memorization rather than written texts.

The Rig Veda contains 1028 hymns and 10,589 verses, reaching a word count of 450,000. Earliest surviving written versions of the Vedas date from 1000 years ago.

Sanskritist J.A.B. van Buitenen noted that European Sanskrit learners in the 18th and 19th centuries found that Brahmins everywhere in India recited the Vedas in the exact same way.

The Indus-Sarasvati Civilization

Spanning thousands of sites largely along the dry Sarasvati river rather than just the Indus valley, this culture built standardized brick structures and established urban sanitation systems. You find that the Indus-Sarasvati civilization was an advanced, highly planned urban culture with sophisticated architecture, sanitation, and a distinct script that appears fully formed without evolutionary traces.

Excavated sites include:

• Harappa and Mohenjodaro on the Indus river;
• Dholavira with its citadel following strict ratios.

Archaeologist R.S. Bisht noted that the Harappan city of Dholavira and its citadel follow a 5:4 ratio specifically prescribed in ancient texts for constructing Vedic fire-altars. Harappa and Mohenjodaro were excavated in the 1920s, revealing an urban civilization dating back approximately 5000 years.

Modern scholarship has completely discarded the nineteenth-century Aryan invasion theory, which falsely assumed a violent conquest of India by a superior European racial stock. Sir Mortimer Wheeler incorrectly used a few dozen un-dated skeletons with non-fatal wounds at Mohenjodaro to claim a violent massacre by invading Aryas.

5. Mapping the Submerged Coastlines

Advanced portolan charts and computer inundation models reveal astonishing correlations with Ice Age geography.

You can investigate mysterious maps that appeared around the end of the thirteenth century. These portolan charts displayed an unexplained, astonishing accuracy of Mediterranean and Ice Age coastlines. Charles Hapgood and other researchers suggest these charts originate from ancient master maps compiled by a high Ice Age civilization. Archives like the Library of Alexandria preserved them over millennia.

Unlike crude medieval maps, portolans used a network of rhumb-lines, precise coastal details, and accurate relative longitudes without showing any signs of gradual evolutionary development from earlier forms. The Carta Pisane, created around 1290, represents the oldest surviving portolan chart and is astonishingly accurate for the Mediterranean. Portolan charts remained unsurpassed by new scientific techniques for 500 years. The Dulcert portolan, dated 1339, shows the total longitude of the Mediterranean and Black Seas correct to within half a degree.

Ancient Cartography

A 1510 Portuguese map investigated by Sharif Sakr portrayed parts of the Indian coast with high fidelity to how they looked 15,000 years ago. On 23 February 2001, Graham Hancock read the e-mail about the 1510 map in India. Charles Hapgood published Maps of the Ancient Sea Kings in 1966, referencing 120 metres of lower sea levels during the Ice Age. His work preceded the publication year of Graham Hancock's book Fingerprints of the Gods in 1995.

The Reinal Map Anomaly

Researcher Sharif Sakr discovers that Jorge Reinal's map contains apparent errors that closely mirror Glenn Milne's inundation map of India at 21,300 years ago. These errors include a large gulf at the Indus mouth, a bulging north-west corner without the Kathiawar peninsula, enlarged Maldive islands, and a mouth-like southern tip. Reinal's map of 1510 shows precise correlations with Milne's 11,500 BC inundation map rather than contemporary geography. A final report on Reinal by Sharif Sakr to Graham Hancock dated 15 August 2001 detailed multiple points of correspondence between Reinal's features and the prehistoric coastline of 11,500 BC. The correlation with the inundation map starts to fade at 13,500 years ago. Both maps show an ancient island at approximately 12 degrees north.

Traditional Okinawan stonemasons looking at the Yonaguni underwater formations immediately identified them as human stone quarries. A traditional Okinawan stone mason, Koutaro Shinza, demonstrated how ancient stonecutters exploit natural joints and fractures in sedimentary rock. A Japanese national TV channel TBS documentary team brought Koutaro Shinza to Yonaguni in 2001 to inspect the undersea ruins after 10,000 years of submersion underwater.

You can observe the specific method used to split stone blocks:

• Wooden wedges are driven into a natural channel in the stone bed.
• The wedges are then soaked with water, causing them to expand.
• As the wedges expand, the stone block splits from its bed, assisted by a chisel.
• The block is removed leaving flat, smooth surfaces on the bed.

Conclusion

The convergence of underwater archaeology, geological inundation models, and worldwide oral traditions forces a complete revision of human prehistory by proving that advanced civilizations existed before the end of the last ice age. You must integrate these disparate disciplines to understand the true fragility of human achievements against planetary cataclysms.

To approach alternative historical research effectively, you should apply these practical rules:

1. Investigate submerged continental shelves where coastal settlements naturally accumulated during the last ice age.
2. Treat global flood myths and king lists as empirical historical data rather than mere allegories.
3. Compare ancient cartographic anomalies against computer models of post-glacial sea level rise.
4. Question orthodox archaeological timelines that dismiss advanced maritime capabilities in prehistoric epochs.
5. Support marine conservation efforts that protect fragile underwater ruins from industrial destruction.

10 Key Ideas

1. Rising seas at the end of the Pleistocene submerged advanced maritime civilizations whose ruins still rest on continental shelves.
2. Anomalous terraced structures and megalithic alignments off the coasts of Japan and India challenge established archaeological timelines.
3. The true origins of Sumerian civilization and its antediluvian cities lie veiled beneath the waters of the Persian Gulf, which was entirely exposed until 14,000 years ago.
4. As continental ice-caps melted between 17,000 and 7,000 years ago, global sea levels rose by 120 metres and swallowed approximately 25 million square kilometres of low-lying land.
5. Massive post-glacial superfloods were concentrated into three short episodes occurring approximately 15,000-14,000 years ago, 12,000-11,000 years ago, and 8,000-7,000 years ago.
6. The Vedic hymns were preserved across millennia with extraordinary accuracy exclusively through oral recitation and strict memorization rather than written texts.
7. The Indus-Sarasvati civilization was an advanced, highly planned urban culture with sophisticated architecture, sanitation, and a distinct script that appears fully formed without evolutionary traces.
8. Ancient portolan charts displayed an unexplained, astonishing accuracy of Mediterranean and Ice Age coastlines that originated from ancient master maps compiled by a high Ice Age civilization.
9. Jorge Reinal's 1510 map contains apparent errors that closely mirror Glenn Milne's inundation map of India at 21,300 years ago.
10. The convergence of underwater archaeology, geological inundation models, and worldwide oral traditions forces a complete revision of human prehistory by proving that advanced civilizations existed before the end of the last ice age.