Some possible keywords for searches about ancient cities and civilizations are: Mesopotamia, ancient civilizations, ancient cities, Sumer, Sumerians, ancient Iraq, Assyria, Uruk, Babylon, Babylonia, Egypt, ancient Egypt, Indus Valley, Indus Valley Pakistan, China, Yellow River, ancient Chinese, Inca, Aztec, Australian aboriginals, Mayan, Olmec.
The Secondary library has a good collection of books about ancient cities and civilizations. Search the Library Catalogue or come and have a look!