It's the smallest sovereign state in the world, and possibly the smallest country in history, so you don't need much of a map. Villa Borghese gardens in Rome is larger that Vatican City. New York's Central Park is three times as big.
Vatican City wasn't recognized as city-state, or even as a legal entity, until a treaty was signed with Italy in 1928. So, in that sense, it's also one of the world's newer countries. Of course, not so long ago it was a different story, when the Papal States ruled most of what is now central Italy, including Rome itself, as shown on a map of Italy from 1796.
As this map shows, the Vatican is a pretty small piece of greater Rome. To the north and east of Vatican City you can see how much bigger the gardens of Villa Borghese are.
As a visitor you're likely to spend most (or all) of your time in central Rome — the inner circle of the city with the Vatican on its left and the word "Roma" at its centre..
We like this map that provides a real graphic representation of how much of Vatican City is covered by St Peter's and the Vatican Museums.
For such a small place, the Vatican certainly has more that its share of artistic and architectural treasures. St Peter's Basilica and St Peter's Square are both remarkable works of art, both inside and out. But then think about all the incredible art housed inside the Vatican Museum. Because there's so much to take in, we always sign up for a skip-the-line Vatican tour!
We like this map, produced by Open Street Maps, because it gives a very clear picture of what's where inside the Vatican.
Vatican City is defined by its ancient walls, shown by the dashed purple line. In this smaller version of the map (you can click on the map or click below to go to a full-size version) you can see a small block at the lower right that has a smaller dashed line running around it.
That block is an area still the subject of a border dispute between Italy and Vatican City, although it seems to be effectively controlled by the Vatican at this point. If you're interested in this kind of thing, there's another narrow strip of disputed land just on the north side of the collonade around St Peter's Square.
We like the Knopf MapGuide series, and they produce a good one for Rome that covers the Vatican as well.It's in the form of a lightweight, easy-to-carry book with cute fold-out maps of the top districts or Rome — that is, the neighbourhoods you're going to want to visit. Every district has an ingenious map that opens up and that's at an easy-to-read scale, showing all the attractions and monuments you want to see, complete with explanations and sightseeing ideas.
The Vatican City section of the Rome MapGuide is particularly good. Knopf MapGuide Rome is our Overall Top Choice.