TEHRAN—A routine road construction project recently yielded a surprising discovery when crews unearthed mysterious subterranean tunnels near Shahr-e Belqeys (“City of Belqeys”) in northeast Iran.

“Remains of ancient underground corridors were discovered a few days ago during a road construction project in Bam village of Esfarayen county,” an expert with Belqeys archaeological site said on Monday.

Shahr-e Belqeys was prosperous during a period from the late Sassanid era to early Islamic times.

“The total length of those corridors is 18 km, and there is a bathroom and a mill on the way, which has not been opened yet,” the expert said.

“Last years, traces of this underground city had been discovered but to protect it, these remains were blocked by the local cultural heritage directorate. Now we reached these ancient structures from another place, which confirms the statements of the local people,” the expert explained.

“The ruins have yielded potteries estimated to belong to the Seljuk period, IlKhanid, and even earlier periods. However, an extensive archaeological excavation is needed to delve into its secrets.”

Archaeological excavations at nearby mounts and hilltops put the antiquity of Belqeys in some 6,000 years. Experts believe that the ancient city enjoyed prosperity from the late Sassanid to the early Islamic eras.

Historical evidence, including a book on the history of Neyshabur, suggests that Shahr-e Belqeys won special attention from Sassanid monarchs of the time, which brought the land a special fortune before the advent of Islam.

Evidence suggests that Shahr-e Belqeys was hectic from the late Sassanid era to a time when Nader Shah Afshar (one of the most powerful rulers in Iranian history) assumed power in the early 18th century.

Belqeys citadel is one of the largest mud-brick fortresses in Iran after the UNESCO-registered Bam citadel. It lies at a short distance from the city of Esfarayen. Remnants of the citadel, family lodgings, irrigation channels, a cistern, and a hypostyle hall are amongst objects so far unearthed in Belqeys during rounds of excavation.

Iran is a haven for ancient troglodytic architecture which is somewhat forgotten, though they are filled with life and creativity. The northwest Kandovan village is one of the most famous examples of troglodytic architecture in the country; its ice-cream cone-shaped homes are resembling that of Turkey’s Cappadocia.

In 2018, the country hosted the 3rd International Troglodytic Architecture Conference in which tens of experts, researchers, and academia discussed troglodyte-associated architecture, culture, and technology.

AM