Singapore is a sovereign island city-state in maritime Southeast Asia. It lies off the southern tip of the Malay Peninsula, bordering the Straits of Malacca to the west, the Riau Islands to the south, and the South China Sea to the east. The country's territory is composed of one main island and 63 satellite islands and islets. It has the second greatest population density in the world.

Vatican City, officially the Vatican City State, is the Holy See's independent city state, an enclave within Rome, Italy. The Vatican City State, also known as The Vatican, became independent from Italy with the Lateran Treaty (1929). With an area of 49 (121 acres) and a population of about 825, it is the smallest sovereign state in the world by both area and population.