Altars of theDeluge

Author's Note

This book records a journey, and tracks the hypothesis that slowly took shape along the way. It is not a work of academic archaeology, nor a systematic exercise in fieldwork: it is the account of a journey through Indonesia, undertaken with my wife Cristina over several weeks between late December 2025 and January 2026, together with the questions that journey raised and the documents, sources and readings that later allowed those questions to be reformulated.

The hypotheses that appear in these pages are offered as interpretive tools, not as proof. Where a fact is debatable, that is stated. Where an interpretation is personal, it is marked as such. The bibliographic notes at the end of each chapter gather the sources on which the historical, archaeological, anthropological and geological claims rest. Any error of fact or interpretation is the sole responsibility of the author.

Out of respect for privacy and for the dignity of the rituals described, the Torajan and Sumbanese families who appear in this book have been partly anonymised. Some of their names do not appear in the text; their generosity does.

The descriptions of funerary and ceremonial rites are written from the position of an invited observer, with full awareness that any account from outside must recognise its own limits.

The hypothesis of convergent responses that runs through this book does not claim to discover cultural convergence from scratch, nor to replace academic work. It enters into dialogue with a broad tradition — independent invention, convergent cultural evolution, human universals, cultural attraction theory and, with caution, the Jungian intuition of archetypes — but here it is used as an interpretive tool: a way of thinking about why human societies with no demonstrable historical contact may produce similar solutions to similar problems, without immediately assigning those similarities to diffusion, common origin or direct transmission.

Prologue

Some things the water erases, and some things remain.

I came back from Indonesia with my boots stained with red mud, several notebooks full of names I struggled to pronounce, and more questions than I had taken with me. Not a bad way to return. Sometimes a journey fails precisely when it confirms too soon what one had hoped to find.

I make my living examining traces and evidence. That imposes a particular kind of caution: not to conclude more than the data allow, not to confuse coincidence with pattern, not to call evidence what is only desire phrased well. But it also teaches something else, less comfortable: that data rarely speak on their own. They have to be touched, compared, held up to the light; one has to accept that a footnote can correct an intuition, and that an intuition can sometimes oblige us to look harder for the footnote.

During that month, among submerged platforms, andesite terraces, funerary houses, painted caves and valleys where the stone still seemed to retain human warmth, I began to suspect something I did not want to formulate too soon. It may be that some resemblances between distant cultures do not always require a secret route, a mother civilisation, or a lost chain of transmissions. Faced with certain problems — death, memory, power, territory, the need to endure — human beings may return again and again to a limited repertoire of responses. Not because those responses are simple, but precisely because they are human.

Cristina would have pointed it out to me if I had written it that way at the beginning. She would have said that we had not yet seen anything. She was right. This book tries to respect that warning. It does not offer closed proof, but the trace of an investigation in motion: what I saw, what I believed I saw, what the sources allowed me to sustain, and what had to be left in suspense.

In the end, the questions worth asking are not always the ones that solve an enigma. Sometimes they are the ones that make it more exact. Indonesia left me with some of those. This book is an attempt not to betray it.

The Edge of a Submerged World

We had left Spain on 20 December and, after landing in Bangkok the following day, remained there until the twenty-fifth: a long stopover imposed by the logistics of the ticket — and by the need to put schedules, luggage and body back together — which ended up serving as a prelude. In the small hours of 25 December, when the plane left Bangkok’s airspace behind and began its descent towards Jakarta, I realised that, for me, the journey did not begin at touchdown, but at the moment of accepting that time, in Southeast Asia, does not entirely obey boarding schedules.

To a traveller in a hurry, that sea might appear to be a simple geographical separation: a sheet of water between thousands of islands. For us it was something else. Through the window I did not see only darkness or flight paths; I saw a drowned continental shelf, a geography mutilated by the rise of the sea. Beneath those shallow waters, though it could no longer be crossed on foot, the ghost of Sundaland still showed its outline.

Some twenty thousand years ago, the sea stood far lower, and Asia did not end where we imagine it today: the Sunda Shelf was, in human terms, a continent.¹ That submerged world was much more than a land bridge between continents. Sundaland held extensive savannahs, tropical forests and river basins on a scale now difficult to imagine when looking at a map of the archipelago. The great rivers of Sumatra and Borneo, which today empty abruptly into the sea, formed part of a larger system, the Paleo-Sunda River, running through fertile valleys before pouring its waters into the South China Sea. Through those valleys our most remote ancestors walked, without need of boats, following Pleistocene fauna and making use of a territory generous in water, vegetation and prey.

The confirmation of that lost landscape does not rest on Atlantean fantasies. It comes from palaeogeography, from genetics,² and from an archaeology beginning to look at submerged territories with different eyes. For decades it was assumed that, if complex human groups had lived in those lowlands, their traces would have been destroyed by the sea, by erosion and by the subsidence of the shelf. Such caution remains necessary. But recent discoveries require, at the very least, that we look again.

Research published in 2025 has given material support to that intuition on the seabed of the Madura Strait, north- east of Java. During dredging operations, thousands of faunal remains were recovered, together with two cranial fragments attributed to Homo erectus, around 140,000 years old, from an ancient river valley now covered by the sea.³ No Atlantis had to be invoked. That seabed had been a habitable plain, a corridor of passage and of life within the great platform of Sundaland: rivers, fauna, prey and the bodies that followed them. It was hard to take in that a whole homeland now lay beneath the water we were flying over.

Thinking of it while crossing those waters had something vertiginous about it. Those 140,000-year-old fossils were the trace of bodies that breathed where now there is only seabed. Nothing of the romantic tableau: bone, sediment and an antiquity that makes us shift the map of human settlement. Homo erectus, the celebrated “Java Man”, would not have been confined to the highlands we now call islands; he may have moved across plains, rivers and corridors that disappeared when the sea advanced. And then a question imposed itself — one best asked without flourish: how much decisive evidence still lies buried under the mud of the archipelago?

The rise of the sea was not a geological anecdote. I was thinking this with my seatbelt still fastened, while the hum of the engines turned the cabin into a sealed chamber. As the glaciers retreated, shorelines moved inland and human populations withdrew towards higher ground, which would eventually become islands. There is no need to turn that process into legend in order to acknowledge its violence. An entire landscape was taken out of reach. And when a community loses its territory, it loses routes, cemeteries, hunting grounds, names, stories and its bearings in the world.

The captain’s voice came over the loudspeaker before I could follow the thread any further: descent into Soekarno- Hatta, ground temperature twenty-nine degrees, local time 4.50 a.m. Cristina stretched beside me, rubbing her eyes and looking out of the window. Below, the darkness of the Java Sea had given way to an ocean of neon lights, car headlights and illuminated towers.

It was Jakarta.

The Indonesian megalopolis extended as far as the eye could reach. From the air, it had the look of a fevered organism: concrete and asphalt, neighbourhoods pressing into one another, saturated motorways and a light without any visible edge. It was not a city made for contemplation; it required entry all at once. Even so, for us it was above all a point of passage. What mattered lay beyond.

We had travelled there to face Gunung Padang, the megalithic site whose most disputed datings had put pressure on archaeological consensus by suggesting, for its possible subsurface structures, an antiquity far greater than accepted chronologies allowed. We also had a second, far less familiar visit on the itinerary: Gunung Tangkil,⁴ a site for which, at present, there are only preliminary indications — recent surveys and local reports, not yet peer-reviewed studies — and which might help us assess whether Gunung Padang was an isolated anomaly or part of a broader megalithic landscape.

The plane touched down with a dry jolt, returning us abruptly to the reality of the twenty-first century. On disembarking, the heat struck at once. Although it was five in the morning, the air outside the terminal was a physical entity, a dense, sticky humidity that clung to clothing and slowed movement. It smelled of aviation fuel, hot asphalt and the unmistakable sweetish odour of kretek (clove cigarette), which seems to permeate every corner of Indonesia.

We collected our luggage without speaking, in that mixture of exhaustion and expectation that precedes difficult journeys. The hotel would have to wait until our return, for a brief rest and a wash: the plan was to go straight to the mountains, with no pause for unpacking and no concession to jet lag. The first day was already beginning, and the past — if that word is of any use in Java — had taken to the hills.

In the arrivals hall, among a crowd of shouting taxi drivers and sleep-heavy travellers, a man was holding a sign with my surname on it. It was Mr. Iskander. We had hired him from Spain through that same hotel — an email with the flight number and approximate itinerary had been enough — and he had already spent weeks with all the details: names, times, destinations. The sign, in that sense, was more greeting than identification.

From the first handshake it was clear what kind of travelling companion we would have. Mr. Iskander did not present himself as a tourist guide; he was a professional driver, and therein lay his value: middle-aged, calm-faced, courteous, cautious, sparing with words. In a country where traffic chaos is the rule and improvisation a way of life, his poise would prove our greatest safeguard. Our communication with him would unfold in English, a language he commanded sufficiently for the journey’s logistics, while he would act as our indispensable interpreter with local people, translating into Indonesian or into local Sundanese dialects when English fell short.

For a moment I thought of the Java Sea — there to the north, though the darkness of the terminal did not let us see it — before the boot lid closed with a hard thud. Mr. Iskander turned the key; the four-wheel drive answered, then joined the flow of vehicles leaving the terminal. With that first pull of asphalt, the journey began.

Java received us with humidity, fuel and clove. I settled beside Cristina.

Cristina, who had remained silent during the final minutes of the landing, leaned towards me as the car left the arrivals area.

“Don’t start looking like you’re writing the preface already.”

“Is it that obvious?” “Very. We haven’t seen anything yet.”

She said it without sharpness, almost tenderly, as one reminds another of something elementary: that the traveller’s first obligation is to accept what lies in front of him, even when it contradicts the scene he had prepared in advance.

In my rucksack I was carrying several printed palaeogeographic maps of the Sunda Shelf. I had consulted them so often before leaving that they had almost become a private superstition. In one of them, the present sea disappeared and the islands were gathered into a single mass of land: Sumatra, Java, Borneo and the Malay Peninsula ceased to be separate names and returned to forming one continuous territory.

Cristina knew them well enough. One evening, weeks before the journey, she had seen me spread them over the sitting-room table and said something I did not forget:

“They don’t look like islands. They look like mountains the water left with only their tops showing.”

I would have spoken of palaeoshorelines, marine regressions and continental shelves. She had seen it at once, in a single physical image: a landscape of which the sea had left only the summits. I put the notebook away and let the lights of Jakarta pass without trying to name them yet.