The volcano that buried two cities—and gave us a word

The Day Two Cities Died

On the morning of August 24, 79 CE, Herculaneum's 4,000 residents watched Vesuvius erupt six miles away. By early afternoon, earth tremors shook the town. At 1:00 AM on August 25, the volcano's eruption column collapsed, sending the first pyroclastic surge toward the Bay of Naples at 100 kilometers per hour. This superheated avalanche of gas and volcanic particles reached temperatures of 400 degrees Celsius. Herculaneum vanished under sixteen meters of material that hardened into tuff, a rock-like substance that would preserve the city for seventeen centuries.

Pompeii, eight miles from Vesuvius, endured a different destruction. Ash and pumice rained down for eighteen hours, burying the city under four meters of volcanic debris. The preserved voids of Pompeii's victims, captured in their death poses, became archaeology's most haunting images. But Herculaneum's pyroclastic flows moved too fast for such preservation. The surge killed instantly, then the mud encased everything—buildings, objects, even organic materials that normally decompose. The two disasters happened hours apart but created entirely different archaeological time capsules.

The wealth gap between the cities was stark. While Pompeii served as a commercial hub with a population of 15,000, Herculaneum catered to Rome's elite. Marble adorned ordinary homes. One villa contained bronze and marble sculptures that now fill rooms in Naples' Archaeological Museum. The House of the Bicentenary featured sophisticated frescoes and a Christian cross—one of Christianity's earliest physical symbols. Senatorial families owned seafront estates here, escaping Rome's summer heat in luxurious otium.

The Excavation That Changed Everything

In 1709, Austrian Prince d'Elbeuf bought land in Resina (modern Ercolano) to build a villa. Workers digging a well shaft struck ancient marble ninety feet down. D'Elbeuf recognized it as Roman workmanship and began tunneling horizontally through the hardened volcanic rock. His workers discovered Herculaneum's theater and extracted columns, statues, and inscriptions. For decades, treasure hunters carved a network of tunnels through the buried city, hauling artwork to European collections. The Herculaneum Women, a set of marble sculptures, reached Dresden in 1736. Not until 1738 did scholars identify the site as ancient Herculaneum.

Pompeii's discovery came in 1748, when engineer Rocque Joaquin de Alcubierre redirected excavation efforts there. Unlike Herculaneum's rock-hard tuff, Pompeii's ash and pumice layers yielded to shovels. By 1763, an inscription confirmed the city's identity. Grand Tour travelers flocked to Pompeii's open-air ruins, where they could walk ancient streets and touch frescoed walls. Herculaneum remained largely inaccessible—buried too deep under material too hard, beneath a living town. Bourbon King Charles III sponsored systematic excavations at both sites, but Pompeii offered faster results and better publicity for the kingdom.

Major excavation at Herculaneum resumed only in 1927 under Mussolini's government, which relocated some Ercolano residents and used pneumatic drills to remove volcanic rock. Archaeologist Amedeo Maiuri directed the work, exposing complete city blocks between 1927 and 1958. The excavation revealed structures Pompeii couldn't match: intact second stories with wooden balconies, rope still coiled in a boat shed, a wooden clothes press with fabric inside. Yet by then Pompeii had seized the public imagination. Herculaneum remained the connoisseur's site, visited by 300,000 people annually versus Pompeii's 2.5 million.

What the Mud Preserved

The Villa of the Papyri, discovered during d'Elbeuf's tunneling in 1750, contained ancient Rome's only surviving library. Workers extracted 1,800 carbonized scrolls from the villa's rooms before abandoning the dangerous tunnels. These papyri, burned black by pyroclastic heat, held Greek philosophical texts—primarily works by Epicurean philosopher Philodemus of Gadara. For 250 years scholars attempted to unroll them; most crumbled. In 2015, researchers at the University of Kentucky used X-ray phase-contrast tomography to read text inside unopened scrolls without destroying them. The 2023 Vesuvius Challenge awarded prizes for AI algorithms that decoded entire passages, revealing previously unknown ancient texts.

Archaeologists found remains of 340 people in Herculaneum, mostly discovered in the 1980s inside twelve boat houses along the ancient beach. For decades scholars believed residents escaped by sea, since so few bodies appeared in the town itself. Then excavators reached the original shoreline, 400 meters from today's coast. Inside the arched chambers lay huddled groups—families who fled to the beach hoping for rescue. Forensic analysis revealed death came instantly from thermal shock. One victim, a soldier, carried a bag of carpenter's tools and 32 gold and silver coins. Nearby lay a pregnant woman with a seven-month fetus, its skeletal structure perfectly preserved.

Wooden objects that rotted away everywhere else in the Roman world survived in Herculaneum. The House of the Wooden Partition retains its folding doors. Beds stand with woven rope mattress supports. A wooden baby cradle sat next to a child's skeleton. Researchers found 300 wooden writing tablets in the House of the Bicentenary, their wax surfaces still bearing indentations from ancient styluses. One table held dice next to a game board. This organic preservation allows unprecedented reconstruction of daily Roman life—the texture of ropes, the joinery of furniture, even ancient diets from preserved food and sewage.

The City We Cannot Reach

Modern Ercolano, population 54,000, sits directly atop 75 percent of ancient Herculaneum. The unexcavated area includes the forum, main temples, and the wealthiest hilltop villas. In 1996, ground-penetrating radar revealed massive structures beneath the town center. The Villa of the Papyri extends far beyond its excavated rooms; scholars estimate it contained at least 3,000 more scrolls in upper-floor libraries. But excavation would require demolishing apartment buildings, churches, and schools. Italian law protects both archaeological heritage and modern residents' property rights. This legal and physical barrier preserves Herculaneum while preventing its study.

The Herculaneum Conservation Project, founded in 2001 through a partnership between the Packard Humanities Institute and Italian authorities, focuses on preserving exposed ruins rather than new excavation. Rising groundwater threatens the site—the ancient water table has risen three meters since Roman times. Exposed wooden structures dry out and crack. In 2010 conservators completed the House of the Relief of Telephus, stabilizing frescoes and protecting wooden elements under climate-controlled barriers. The project spent over 20 million euros by 2015 but excavated nothing new. Preservation trumps discovery.

Yet technology offers hope without shovels. In 2019, researchers used muon tomography—detecting particles from cosmic rays—to map buried structures without excavation. The technique revealed room layouts and wall thicknesses beneath Ercolano's streets. Combined with AI-powered scroll reading, these methods let archaeologists study Herculaneum's buried portions virtually. The Vesuvius Challenge promises more discoveries as algorithms improve. Perhaps Herculaneum's greatest contribution lies ahead: a Roman city studied entirely through walls, its streets never walked by modern feet, preserved in perpetual twilight beneath an Italian town that both protects and imprisons antiquity's richest time capsule.