In the first century AD, a Roman scholar named Josephus, who was both revered and allegedly known to get a little creative with his facts, recounted tales of the great King Nebuchadnezzar II’s palace in Babylon 600 years earlier.

Josephus wrote of the Babylonian palace: “Any attempt to describe it would be tedious: yet notwithstanding its prodigious size and magnificence it was finished within 15 days. In this palace he erected very high walks, supported by stone pillars; and by planting what was called a pensile paradise, and replenishing it with all sorts of trees, he rendered the prospect an exact resemblance of a mountainous country. This he did to gratify his queen, because she had been brought up in Media, and was fond of a mountainous situation.”

And with the inky flourish of that period, he set his own garden situation in motion that has surely had Nebuchadnezzar rolling in his grave with laughter for nearly three millennia.

See, Josephus helped originate the belief that the Babylonian King was responsible for a wondrous vertical garden that became known as the Hanging Gardens of Babylon. Its contents and the technical innovation needed to create it were so incredible, that it was deemed one of the Seven Wonders of the Ancient World.

Yet, no one could find evidence that the Hanging Gardens of Babylon ever existed. The remains of the ancient Mesopotamian city have been thoroughly excavated with no trace of an inventive system of gardens to be found, and the writings of a prolific Nebuchadnezzar studied without finding word of a feat that he surely would have documented.

But in 2013, the answer to this enduring mystery may have been uncovered by scholar Stephanie Dalley, who found evidence that old Neb probably had nothing to do with the Hanging Gardens.

In fact, signs now point to the arch rival of the Babylonians, King Sennacherib, who ruled over Assyria—and the routing of Babylon—300 years earlier. Turns out, for thousands of years, the Babylonians have likely been taking credit for one of the greatest feats of the Assyrians in what is surely one of the better—albeit inadvertent—acts of informational warfare.

The Garden of Eden. The Secret Garden. The Garden of Live Flowers. The fantastical dreams of hideaways filled with lush and exotic plant life have populated our cultural imaginings from the beginning.

So it’s no surprise that the idea of a garden that seemed to hang over the heads of its onlookers and dazzled with its diversity and ingenuity captured the cultural imagination. Or that scholars began to doubt its very existence. Maybe the Hanging Gardens of Babylon were just another invention of the imagination.

That was the state of affairs when Dalley, an Assyriologist at the University of Oxford and one of the rare scholars who can read cuneiform, was studying an ancient stone prism on which Sennacherib wrote about his many exploits. The Assyrian king ruled over a large empire ranging roughly from modern day southern Turkey to Israel, and in his writings, he mentioned another achievement.

“I raised the height of the surroundings of the palace to be a wonder for all peoples,” Sennacherib wrote, going on to describe “a high garden imitating the Amanus mountains I laid out next to the palace with all kinds of aromatic plants, orchard fruit trees, trees that sustain the mountains, and Babylonia as well as trees that bare wool planted within it.”

This was Dalley’s smoking gun. “It began to look as if we simply had the wrong place, the wrong king, the wrong story altogether,” Dalley told PBS in a 2014 episode of Secrets of the Dead.

With this new lead, she began to examine the writings and wall carvings that came from Sennacherib’s palace in Nineveh, near current-day Mosul, Iraq, and she found the further evidence that she needed.

While the authorship and location of the Hanging Gardens has been in questions for hundreds of years, two aspects were generally agreed upon. First, they were arranged in some sort of terrace system that gave the impression that they were “hanging.” Second, they featured a cutting-edge irrigation system that carried water from the garden’s base to the top terraces in order to keep the foliage there alive.

Dalley set out to prove that both of these things could have been possible at the site in Nineveh and under the guidance of Sennacherib.

It’s impossible to prove her theory with 100-percent certainty—that would require extensive research at the site in Nineveh itself, which is impossible given the dangerous, ongoing security situation in Mosul—but what Dalley did find supports her conclusions and suggests that the Hanging Gardens were a spectacular feat of artistry and engineering.

And that they should be rightly known as the Hanging Gardens of Nineveh.

For this verdant wonderland to be possible, Sennacherib had to move water from the distant Tigris River to his palace at Nineveh to supply the immense daily needs of the garden. He did this by creating a precise system of canals that diverted water through the valley for 60 miles.

For every kilometer the water traversed, it would drop one meter in elevation, slowly making its way to the capital city. At one point, the canal system had to cross a stream. So the Assyrians, living over 600 years before the Roman Empire began and Jesus was born, crafted an aqueduct that allowed their canal to hop over the water and continue on its way.

Dalley visited this system several years ago, and traces of Sennacherib’s work are readily available… helped along by the fact that the king was not shy about self-promotion.

At the beginning of the canal system are giant stone wall carvings in which Sennacherib brags about his invention and equates himself with the gods. The aqueduct features similar notations, with Sennacherib essentially signing his name to the achievement like a painter would sign his canvas, along with the not so humble descriptor, “the king of the world, the king of the land of Assyria.”

As Dalley told PBS, “There’s no doubt at all who built this. Not modest at all. He wanted to make sure his legacy lasted forever.”

The exact location of the garden in the palace compound is harder to pinpoint, but Dalley has an idea of where she thinks it may have lived, and several stone carvings from the palace give us an idea of what it would have looked like.

True to the tales that have been passed down through the ages, it most likely was a terraced system, with a a lake at the bottom and rows of local and exotic plant life stepping their way to the top.

And this brings us to Sennacherib’s last amazing invention—watering those plants at the top.

Nearly 500 years after the Hanging Gardens are now thought to have been created, a Greek scientist named Archimedes invented what is known as the “Archimedes screw.” It allowed water to be transported vertically, and it is still in use today. But it turns out, Sennacherib was centuries ahead of him. He developed—and wrote about, of course—a cast bronze screw system that he used to lift water from the lake at the bottom of the pyramidal gardens to the top, to provide the terraced plants with over 300 tons of water a day.

In 2013, Dalley published her findings in The Mystery of the Hanging Garden of Babylon, and, with that, most likely ended Nebuchadnezzar’s reign as the King of Gardeners.

She also lifted this world wonder out of the dubious distinction of being the only one of the seven which had disappeared without a trace. In the annals of spectacular fictional gardens, the Hanging Gardens of Babylon may now be expelled.

And Sennacherib is finally poised to get his due, something that this proud king certainly would have appreciated. The Hanging Gardens weren’t Nebuchadnezzar’s spectacular gift to his homesick queen; they were more likely a creation of Sennacherib meant to be “a wonder for all peoples.”

“The thing is, it’s not just a garden is it? It’s a world wonder on several different counts,” Dalley said. “This whole waterworks is part of what makes the Hanging Garden a world wonder. And it shows the character of Sennacherib. He’s not afraid of a big project and he has the expertise to carry it out. And it works when he’s done it.”