Vatican City

Vatican City, officially Stato della Città del Vaticano, which translates literally as "State of the City of the Vatican", is a landlocked sovereign city-state whose territory consists of a walled enclave within the city of Rome, the capital city of Italy. It has an area of approximately 44 hectares, and a population of just over 800. Vatican City was established in 1929 by the Lateran Treaty, signed by Cardinal Secretary of State Pietro Gasparri, on behalf of the Holy See and by Prime Minister Benito Mussolini on behalf of the Kingdom of Italy.

Vatican City is ruled by the Bishop of Rome—the Pope. The highest state functionaries are all Catholic clergymen of various national origins. The Popes have generally resided in the area that in 1929 became Vatican City since the return from Avignon in 1377, but have also at times resided in the Quirinal Palace in Rome and elsewhere. (source) I sent this card to myself when I visited Vatican City on 19th of September 2010.