This is something cool I learnt today!So, you may have heard how the great wall of China is the only human structure visible from space. Or how that claim is actually bollocks and totally made up :)In reality, the largest human-made structure visible from space is El Ejido, a large complex of plastic greenhouses in the province of Almería, southeastern Spain. The complex covers about 26 thousand hectares (100 square miles) in the province of Almería, Andalucía, Spain and is also known as the "Plastic sea" for obvious reasons.