An enclave is a territory that is entirely surrounded by the territory of only one other state or entity. Such territory can be a small territory as part of a larger one. Enclaves may also exist within territorial waters. Enclave is sometimes used improperly to denote a territory that is only partly surrounded by another state. Many enclaves are also exclaves, but some are not, for example Vatican City and San Marino and Lesotho are completely enclaved sovereign states.
Land for the Captain Cook Monument was deeded outright to the British government by the independent nation of Hawaii in 1877.
The John F. Kennedy Memorial at Runnymede, United Kingdom, placed on land given to the United States in 1965
Vatican City, officially the Vatican City State, is a landlocked sovereign country, city-state, microstate, and enclave within Rome, Italy. It became independent from Italy in 1929 with the Lateran Treaty, and it is a distinct territory under "full ownership, exclusive dominion, and sovereign authority and jurisdiction" of the Holy See, itself a sovereign entity under international law, which maintains the city-state's temporal power and governance, diplomatic, and spiritual independence. The Vatican is also a metonym for the pope, Holy See, and Roman Curia.
Vatican City
The Vatican obelisk in St. Peter's Square was brought to Rome from Egypt by Caligula
Musicians of the British Army's 38th (Irish) Brigade playing in front of St. Peter's Basilica in June 1944
View of St. Peter's Square from the top of Michelangelo's dome