There’s some speculation over whether this list’s entry existed in real life or just in a writer’s imagination. It certainly would’ve been a challenge to build – with its epic 65ft high terraces and complex machinery, it seems like an engineering masterpiece. Legend has it, that The Hanging Gardens of Babylon were built near the Euphrates River in modern-day Iraq as a gift from Babylonian King Nebuchadnezzar to his wife, Amytis, who was homesick for the verdant mountains of the Median Empire. Whether a fairytale or true story – the gardens looked like a green paradise on Earth.