Turkey Earthquake: Gaziantep Castle—Dating Back to Roman Empire—Collapses

A 7.8 magnitude earthquake shook southern Turkey and northern Syria on Monday morning, destroying buildings and killing more than 1,000 people. Among the rubble lie the remains of an ancient landmark that was built more than 2,000 years ago.

Gaziantep Castle, which lies in the middle of the city of the same name in the south of Turkey, was leveled by the earthquake. The east, south and southeast parts of the historical castle in the central Şahinbey district were destroyed by the earthquake, and debris was scattered on the road, reported state-run Anadolu Agency, adding that the retaining wall also collapsed.

The structure was originally built as a small observation point by the Hittite Empire in the second millennium B.C, but was later expanded by the Roman Empire in the second and third century A.D. The fortress underwent additional expansion and renovation in the sixth century, under the Byzantine Empire of Justinian I, to become the castle that was visited by tourists.

Gaziantep Castle
Photo of the Gaziantep Castle in southeastern Turkey. The ancient castle has partially collapsed due to an earthquake in Turkey. OMAR HAJ KADOUR/Getty

Beneath the castle lies a series of tunnels and caves dating back thousands of years. These underground water structures were included on the UNESCO World Cultural Heritage Tentative List. It is unclear at time of writing what damage they sustained. Many of the city's inhabitants have taken to Twitter to express their grief for its demise.

"Symbol of my hometown gone," user ReisenOnTank said. "Heartbreaking."

"Truly awful when such history is erased in an instant," said user Morderkaj.

The dome and eastern wall of the historical Şirvani Mosque, located next to the castle and believed to have been built in the 17th century, have also partially collapsed, according to Anadolu Agency.

Earthquakes are not uncommon in Turkey as the country sits on top of a series of major fault lines. The 7.8 magnitude earthquake is equivalent to the release of just over 500 megatons of TNT, according to the U.S. Geological Survey.

Gaziantep Castle
Photo of Gaziantep Castle, a structure that has stood in southeastern Turkey for over 2,000 years and partially collapsed in the recent earthquake. OMAR HAJ KADOUR/Getty

"The magnitude of shaking that is felt on the surface is both a function of the amount of energy released, the size of the earthquake, but also how far that energy is released below the surface," Karl Lang, assistant professor at Georgia Tech University's School of Earth and Atmospheric Sciences, told CNN. "If it is a shallow earthquake, then it can be very dangerous.

"What's really unusual here is that it's a very large earthquake that is also close to the surface."

The quake was centered around 20 miles from Gaziantep at a depth of about 11 miles. The primary quake was followed by a series of at least 20 aftershocks—smaller earthquakes that represent minor readjustments along fault lines after the initial main shock—which are also believed to have caused significant damage, the extent of which is yet to be determined.

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