Vatican City

Vatican City is the smallest state in the world, at less than half a square kilometre, and a little more than half its surface is taken up by the Vatican Gardens, created in the thirteenth century and remodelled during the Renaissance. That walled enclosure works as a green island in the centre of Rome: it brings together stone pines, cypresses, holm oaks, palms and collections of plants that arrived from all over the world as diplomatic gifts, alongside a rose garden and a small Mediterranean wood. Its natural value is above all that of an urban refuge, with blackbirds, warblers, greenfinches, feral parakeets, garden dormice, bats and peregrine falcons that hunt above the domes. Like all of Rome, it forms part of the area that every winter receives enormous flocks of starlings from northern and eastern Europe.