The United States of America is vast. It features 19,924 km of coastline and in comparison is about half the size of Russia; about three-tenths the size of Africa; about half the size of South America (or slightly larger than Brazil); slightly larger than China; and almost two and a half times the size of the European Union. With its 50 official states, the country has everything to offer a visitor. The Climate is mostly temperate, but you will find tropical conditions in Hawaii and Florida, Arctic conditions in Alaska, and heat in the semiarid great plains west of the Mississippi River, and arid regions in the Great Basin of the southwest. The country has a vast central plain, mountains in west, hills and low mountains in east; rugged mountains and broad river valleys in Alaska; and rugged, volcanic topography on the island of Hawaii.This is United States of America.