National Monument to Vittorio Emanuele II
Although considered as the most ugliest building in Rome, from here you can get the best views of Rome and surroundings, and particularly of Roman Forum located just next to the monument.
A 360 degree view of Rome can be obtained walking from one side to another side. Climbing up can take some 10 minutes, but its really worth it. As alternative you can take an elevator (7 EUR).
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