Which city has a country inside it?

Rome contains Vatican City, an independent state of about 0.44 square kilometres entirely surrounded by the Italian capital - the smallest country in the world, and the only one you can walk across during a lunch break.

It exists because of a sixty-year standoff. When the new Kingdom of Italy annexed the Papal States in 1870, the popes refused to accept it and declined to leave the Vatican, calling themselves prisoners. The dispute was only settled by the Lateran Treaty of 1929, which recognised the tiny state and paid compensation for the lost territories.

Rome also contains a second sovereign oddity, which almost nobody notices: the Sovereign Military Order of Malta holds extraterritorial status over two buildings in the city, issues its own passports and stamps, and maintains diplomatic relations with over a hundred countries, despite having no territory in the ordinary sense. San Marino, further north, is a third independent state inside Italy - which gives one country more enclaved states than the rest of the world combined.