Vatican City, Vatican City

You cannot visit Rome without visiting the Vatican City! It is literally in Rome but its own country, Its amazing really. It is basically a walled enclave within Rome and is about 110 acres this makes it the smallest independent state in the world by both area and its population. 

The Vatican City is an ecclesiastical state, this means that it is ruled by the Bishop of Rome (the Pope). The  Vatican's climate is the same as Rome's (Please see Rome for more details of the climate and temperature details.) 

The main thing to view in the Vatican City are the Vatican Gardens which account for more than 1/2 of the territory. These gardens were established in the Renaissance era and cover approximately 57 acres of the Vatican City. Other attractions of the Vatican City are obviously St. Peter's Basilica which is arguable one of the prettiest Cathedrals in the world. This is probably because it is the center of the entire Catholic religion so it would have to be the finest one in the world. The Vatican Museum should also be seen because it will give you all the factual information of the Vatican and the previous Popes etc. The Sistine Chapel should also be visited. 

You can stay just outside the city walls the closest is probably Hotel Columbus which is only a 3 minute walk (250m) or you could stay more in the city center of Rome which would mean that you could see Rome's attractions more easily.