Most of the state is tropical jungle; cities are clustered along navigable waterways and are accessible only by boat or plane. The capital and largest city is Manaus, a modern city of 2.1 million inhabitants in the middle of the jungle on the Amazon River 1,500 km upstream from the Atlantic Ocean. Nearly half the state's population lives in the city; the other large cities, Parintins, Manacapuru, Itacoatiara, Tefé, and Coari are also along the Amazon River in the eastern half of the state.