A ecumenopolis was a planet or moon whose primary terrain was urban. An ecumenopolis often led to the destruction or changing any native species on the planet. A typical ecumenopolis would have over 600 billion people. A large ecumenopolis, such as Jarreban, would have a population in the trillions. The first recorded ecumenopolis in history was Imperial Era Earth. An ecumenopolis often had massive energy requirements and resources. This need for energy was supplied by gigantic solar arrays on every building. An ecumenopolis could import its food and other resources from nearby worlds. A world with a high enough population could be mistaken for an ecumenopolis because of the city lights.