You are looking at the spiritual center of ancient Rome, an enclosed area atop the Capitoline Hill (mons Capitolinus); click here for more information about the geography and early history of this, the most famous of Rome's seven hills. At the center of this square, on the south summit of the hill, is the greatest of all Roman religious buildings, the great Temple of Jupiter Capitolinus. The Area Capitolina is crowded with smaller temples and altars, statues, and dedications, but the huge temple dwarfs everything around it.
This reconstruction drawing and this labeled model show the temple and the Capitoline in relation to their surroundings, including the Forum, while this model shows how Jupiter's temple dominates the central part of the city.
Today is one of the festival days honoring Jupiter, and you see the emperor sacrificing in front of the temple. Drawn by curiosity mixed with awe, you walk closer to the temple to see what you can learn.
Triumph
Temple of Jupiter Tonans