Built between 1885 and 1911 to celebrate the uniting of Italy as a nation, and dedicated to the first King of all Italy, Vittorio Emanuele II. Of course, the monarchy only lasted another thirty years after the completion of the Vittoriano, and most Italians would still scoff at the idea of unity, but the monument remains and is still important for those Italians with thoughts of nationhood. Guarded by soldiers, a flame burns on the front terrace of the monument to mark the grave of an unknown soldier; this is the Altar of the Fatherland, the Altare della Patria.
Tourists from other parts of Italy make a beeline for the Vittoriano, but it is worth visiting even if you feel no such patriotic awe or affection. From the upper levels there are great views over Rome, and in 2007 a glass lift (elevator) was installed to take paying visitors up to the very top of the monument, on the roof between the two crowning statuary groups. It's a good place to begin your sightseeing in Rome, since it gives you an unmatchable overview of the city and its geography.