Underground
We live on a thin skin. Beneath it are voids that water spent millions of years dissolving, shafts people sank looking for salt and gold and coal, cities carved out of soft rock by populations hiding from armies, and a biosphere of microbes that may outweigh everything walking around up here. Below all of that is a planet we have never seen and never will, the deepest hole ever drilled reached twelve kilometres and stopped, which is not quite a third of the way through the crust, let alone the six thousand to the centre. Everything we know about the inside of the Earth we learned by listening to earthquakes. The underground is also where the record is kept: it buried Pompeii and preserved it, held Tutankhamun for three thousand years, and kept the oldest art anyone has found on walls that no daylight ever reached. This archive goes down through all of it, the caves, the mines, the digs, the tunnels, the life, the descent, the deep earth, and the underworld people imagined long before they could measure any of it.
A chronological documentary of 647 moments spanning 4000 BC–2026 on Loreline.
Curated by Olivier · last updated 2026-08-22
Eras
- Geology, What the ground is made of and how it moves. Plate tectonics and the mantle, the rock cycle, volcanoes and magma chambers, aquifers and groundwater, the deepest boreholes ever drilled, and the instruments that read a planet nobody can see into.
- Earthquakes, The ground failing. Faults and how they rupture, seismology and the seismograph, the big ones from Lisbon to Tōhoku, early-warning systems, building codes and what survives, and the search-and-rescue work in the first seventy-two hours.
- Soil & Worms, The living few metres at the top. Soil horizons and how long they take to form, the worms Darwin spent forty years on, mycorrhizal networks and the fungi that trade with roots, burrowing animals, the seed bank, and the erosion that removes it all faster than it accumulates.
- Caves, The hollow places. Limestone and karst, stalactites and stalagmites, lava tubes and ice caves, crystal chambers, the biggest caverns yet found, and how a cave is surveyed and mapped.
- Caving, Going in. Sport caving and expedition caving, the deep systems of Krubera and Veryovkina, rope work and sumps, cave diving and its fatality rate, the Thai cave rescue of 2018, and the people who keep going back down.
- Cave Life, What lives in permanent darkness. Bats and their colonies, blind fish and cave salamanders, troglobites that lost their eyes and pigment, extremophiles in deep rock, and the microbiology of places sunlight never reaches.
- Cave Art, The oldest pictures. Chauvet, Lascaux, Altamira, El Castillo and the Sulawesi hand stencils, ochre and charcoal and blown pigment, the dating arguments, and the replica caves built because human breath was destroying the originals.
- Archaeology, Digging up what people left. Stratigraphy and the trench, Pompeii and Herculaneum, Çatalhöyük and Sutton Hoo, ground-penetrating radar and LiDAR, radiocarbon dating, and the finds that rewrote a chronology.
- Tombs, Burial as architecture. Tutankhamun and the Valley of the Kings, Qin Shi Huang's terracotta army and the unopened mound, Newgrange and the passage graves, mummies and bog bodies, and the grave goods that tell you what a society valued.
- Catacombs, The cities of the dead beneath cities. Rome's Christian catacombs, the Paris ossuary and its six million, the Capuchin crypts, Odesa and Naples, and the tunnels people later used to hide, smuggle or party in.
- Rock Churches, Buildings cut down into the ground instead of up from it. Lalibela's monolithic churches, Petra, the Cappadocian settlements of Göreme and Derinkuyu, the cliff monasteries of the Judean desert, and the ceilings that were once solid stone.
- Mines, Taking the rock out. Coal and copper and salt, the shaft and the drift, room-and-pillar and longwall, the cage and the headframe, the mining town, the machines that replaced ten thousand men, and the pits that closed.
- Gold Rush, Sudden wealth underground. California in 1849, the Klondike and Witwatersrand, the panning and the claim, boomtowns built and abandoned in a decade, and the artisanal gold miners still going down on ropes today.
- Lithium & Cobalt, The mining the energy transition runs on. Lithium brines and hard-rock spodumene, cobalt in the Congo and the artisanal pits, rare earths and their processing, deep-sea nodules, and the supply chains behind every battery.
- Mining Disasters, When it goes wrong. Firedamp and coal-dust explosions, roof falls and floods, Aberfan and Courrières and Senghenydd, the Chilean thirty-three and their sixty-nine days, mine rescue teams, and the inquiries that followed.
- Tunnels, Boring through. The tunnel boring machine and the roadheader, the Channel Tunnel and the Gotthard Base, metro construction under a live city, sewers and utility tunnels, and the deep repositories being built to hold nuclear waste for a hundred thousand years.
- Secret Tunnels, Underground because it had to be hidden. Escape tunnels under the Berlin Wall, the Cu Chi network, smuggling and cartel tunnels, wartime bunkers and command centres, the Underground Railroad, and the places people went to survive a government.
- Myth, The underworld as an idea. Hades and Sheol and Xibalba, hollow-earth theories and the people who believed them, the journey down and back in myth and literature, and the persistent human conviction that something is under there.
…and 647 more moments. Full text archive: /loreline-text/underground.md