A British academic has uncovered an explanation for why archaelogists have never been able to locate the site of the fabled Hanging Garden of Babylon. And the answer - which comes after scores of digs turned up nothing - seems blindingly obvious. According to Stephanie Dalley, of Oxford University, the Hanging Garden was not actually in the ancient city of Babylon but 300 miles away in Nineveh, in modern day northern Iraq. After 18 years of study, she has concluded that the garden was built by the Assyrians in the north of Mesopotamia rather than by their great enemies the Babylonians in the south. Dr Dalley has amassed a wealth of evidence to show that the garden - one of the original seven wonders of the world - was created at Nineveh, in the early 7th century BC. She believes her research shows that the feat of engineering was achieved by the Assyrian king, Sennacherib, rather than the Babylonian king, Nebuchadnezzar. The new evidence emerged from deciphering Babylonian and Assyrian scripts and reinterpreting later Greek and Roman texts. They included a 7th-century BC Assyrian inscription that, she discovered, had been mistranslated in the 1920s, reducing passages to "absolute nonsense". Dr Dalley, an expert in ancient Middle Eastern languages, said she was astonished to find Sennacherib's own description of an "unrivalled palace" and a "wonder for all peoples". He describes the marvel of a water-raising screw made using a new method of casting bronze -- and predating the invention of Archimedes' screw by some four centuries. Dr Dalley said this was part of a complex system of canals, dams and aqueducts to bring mountain water from streams 50 miles away to the citadel of Nineveh and the hanging garden. The script records water being drawn up "all day". Recent excavations have found traces of aqueducts. One near Nineveh was so vast that Dr Dalley said its remains looked like a stretch of motorway from the air, and it bore a crucial inscription: "Sennacherib king of the world ... Over a great distance I had a watercourse directed to the environs of Nineveh ..." Having first broached her theory in 1992, Dr Dalley is now presenting a mass of evidence in a book, The Mystery of the Hanging Garden of Babylon. She is convinced that Sennacherib's garden fulfils the criteria for a wonder of the world -- "magnificent in conception, spectacular in engineering, and brilliant in artistry". Sennacherib's palace, with steps of semi-precious stone and an entrance guarded by colossal copper lions, was magnificent. His garden boasted terraces, pillared walkways, exotic plants and trees, and rippling streams. Little of Nineveh -- near present-day Mosul -- has so far been explored, because it has been judged too dangerous until now to conduct excavations.