An earthquake dropped a Silk Road city under a Kyrgyz lake

Divers surveying the shallows of Lake Issyk-Kul in Kyrgyzstan have mapped the remains of a medieval trading city that vanished when an earthquake struck the shoreline at the start of the 15th century. The settlement, known as Toru-Aygyr, sat on a northern branch of the Silk Road connecting China to the Mediterranean before the quake sent it under the lake’s rising water. Six centuries later, an international team of archaeologists has recovered enough of it — brick buildings, a stone millstone, a Muslim cemetery — to reconstruct how the city lived and how abruptly it disappeared.

A millstone and a mosque in three feet of water

The expedition, run jointly by the Institute of Archaeology of the Russian Academy of Sciences and Kyrgyzstan’s National Academy of Sciences, surveyed four underwater zones off the lake’s northwestern shore. In the first zone, divers found several buildings made of kiln-fired brick, including one that still held a stone millstone once used to grind grain into flour. Collapsed walls and scattered wooden beams nearby point to a settlement that was functioning right up until the moment it went under, rather than one abandoned gradually over years.

A separate structure decorated on the outside may have served as a mosque, a bathhouse or a madrassa, an Islamic school — researchers surveying the site at depths of just three to thirteen feet have not settled on which. Whatever its exact function, its presence tells them the city had grown well beyond a simple caravan stop by the time disaster struck.

Valery Kolchenko’s Pompeii comparison

Valery Kolchenko, head of the Kyrgyz side of the expedition, has described the site as “a city or a major trading hub on a key section of the Silk Road.” He said the earthquake that ended it struck at the beginning of the 15th century, and that the destruction it caused can be compared to Pompeii, the Roman city buried instantly by a volcanic eruption in 79 A.D.

Kolchenko’s team believes residents saw the danger coming. “According to our assessment, at the time of the disaster, the residents had already left the settlement,” he said, suggesting tremors or a receding shoreline gave people enough warning to flee before the ground gave way. The aftermath reshaped the region far beyond one city: “After the earthquake disaster, the region’s population changed drastically, and the rich medieval settlement civilization ceased to exist,” Kolchenko said. Nomadic herders replaced the urban trading centers that had lined the shore, and the area today holds small villages rather than the commercial hubs that once stood there.

Why a multicultural crossroads turned Muslim

Before the earthquake, Toru-Aygyr had already gone through a religious transformation that shaped what divers eventually found. Expedition leader Maksim Menshikov, of the Institute of Archaeology of the Russian Academy of Sciences, has explained that the region came under the control of the Karakhanid dynasty around the 10th century, a Turkic state whose subjects practiced a mix of faiths, including Tengrianism, Buddhism and Nestorian Christianity. Islam spread more widely across Central Asia in the 13th century under the Golden Horde, the Mongol successor state, and Toru-Aygyr’s residents increasingly traded with fellow Muslims as the religion took hold in the city.

Menshikov also pointed to the city’s place in the wider Silk Road network the Karakhanids controlled, noting that Chinese sources of the period record the area even though China itself never held it directly. “The Chinese considered this territory a zone of their interests, but they could not control it,” he said. “Nevertheless, we see that this location is reflected in Chinese sources.”

A cemetery eroding at the bottom of the world’s eighth-deepest lake

The clearest evidence of that religious shift sits in the second surveyed zone: a Muslim necropolis dated to the 13th or 14th century, laid out so that burials face Mecca. Researchers recovered the remains of two individuals for anthropological study, both positioned according to Islamic funerary custom. As researchers examining the find have noted, a formal cemetery — rather than scattered graves — signals a settled community with established religious practice, not a waypoint nomads simply passed through.

The cemetery’s location underwater is itself a clue to how fast the city fell. A graveyard only makes sense on dry land, so its presence beneath the lake means the ground it sat on collapsed or flooded abruptly rather than sinking gradually as water levels crept up over decades. That fits the geology of Issyk-Kul, the eighth-deepest lake in the world at 2,192 feet and the second-largest mountain lake after Lake Titicaca, sitting in the young, seismically active Tian Shan range where the lake’s surface now stands roughly 26 feet higher than it did in medieval times. Samples pulled from the site have been sent for radiocarbon dating, which should eventually pin down how long Toru-Aygyr thrived before the earthquake ended it.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

More from Morning Overview