Hello how may I help you? I'd like to know what river goes through Prague. Sure I can help with that. The river that runs through Prague is called the Vltava River. Was this helpful? Yes that is exactly what I was looking for. Is there any other info I can help provide? Yes I'd like to know what is the biggest city in the world? The biggest city in the world by population is Tokyo, Japan with almost 38 million residents What is the biggest city in the USA? In the United States, New York City is the most inhabited city. Is there anything else I can help with? Yes I'd like to know what the biggest city in the world is by size not population That would also be New York City.