Long before modern engineers drove tunnels beneath rivers, ancient writers claimed one already existed under the Euphrates at Babylon. The story, passed down by classical authors, describes a brick-lined passage sealed with bitumen that connected the two halves of the city, letting people cross below the river without boats or bridges. If real, it would rank among the boldest engineering feats of antiquity. The catch: not a single brick of it has ever been found.
The main account comes from Diodorus Siculus, a Greek historian writing in the 1st century BCE, with later echoes from Philostratus in the 3rd century AD. According to Diodorus, builders first diverted the Euphrates, dug the tunnel in the dry riverbed, then let the water flow back over the top. He gave the passage specific dimensions — 12 feet high and 15 feet wide — with massive bronze gates at each entrance. The project is usually credited to Queen Semiramis, though some versions name another Babylonian ruler.
Historians are sceptical for good reason. Both writers lived centuries after the supposed construction and relied on older traditions rather than anything they had seen. Excavations at Babylon have turned up city walls, palaces, temples and endless artefacts, yet zero evidence of a tunnel. Shifting river channels, floods and centuries of human activity could have buried or destroyed remains, but until something surfaces, the tunnel stays firmly in legend territory.
Semiramis herself complicates matters. She was probably based on Shammuramat, a genuine Assyrian queen of the 9th century BCE, but her legend snowballed over time. Ancient storytellers credited her with founding cities, conquering huge territories and building monuments across the Near East, and many historians treat projects pinned to her name as later embellishments.
Still, the idea isn't absurd. Mesopotamian builders were genuinely skilled with water: they dug vast canal networks, built embankments, diverted rivers and waterproofed structures with bitumen, the natural petroleum tar the region had in abundance. Babylon was famous for its urban planning and hydraulic works. A river tunnel would have been an extreme challenge, but it sits within the range of what these civilisations could plausibly attempt.
For travellers drawn to Iraq, the story adds another layer of mystery to a site already famous for unresolved riddles — the tunnel's fate closely mirrors that of the Hanging Gardens of Babylon, celebrated in ancient texts but never conclusively located by archaeologists. Whether you stand among the reconstructed walls at Babylon or read about it from home, the Euphrates Tunnel is a reminder that some of the world's greatest wonders survive only as words.
The takeaway for anyone planning a trip to the region: Babylon rewards visitors who arrive knowing its stories, including the ones that may never be proven. Fact, exaggeration or pure legend, the tale of crossing beneath the river unseen is part of what makes this ancient city so compelling.
Story via Amusing Planet.