Saint Kitts and Nevis, officially the Federation of Saint Christopher and Nevis, is a small island nation located in the Leeward Islands chain of the Lesser Antilles in the Caribbean Sea. Comprising the two islands of Saint Kitts and Nevis, it is notable for being the world's smallest sovereign federation. With a population of approximately 53,192 and a total area of 261 km², the nation maintains a tropical climate and a strong focus on tourism and international finance. The country is a Commonwealth realm, with the British monarch serving as the head of state.