• Roman Forum: Two thousand years ago, most of the known world was directly affected by decisions made in the Roman Forum. Today, classicists and archaeologists wander among its ruins, conjuring up the glory that was Rome. What you'll see today is a pale, rubble-strewn version of the once-majestic site — it's now surrounded by modern boulevards packed with whizzing cars.
  • Palatine Hill: According to legend, the Palatine Hill was the site where Romulus and Remus (the orphaned infant twins who survived by being suckled by a she-wolf) eventually founded the city. One of the seven hills of ancient Rome, Il Palatino is enhanced by the Farnese Gardens (Orti Farnesiani), laid out in the 1500s on the site of Tiberius's palace.
  • The Colosseum: Rome boasts only a handful of other ancient monuments that survive in such well-preserved condition. A massive amphitheater set incongruously amid a maze of modern traffic, the Colosseum was once the setting for gladiator combat, lion-feeding frenzies, and public entertainment whose cruelty was a noted characteristic of the Empire (just ask Russell Crowe). All three of the ancient world's classical styles (Doric, Ionic, and Corinthian) are represented, superimposed in tiers one above the other.
  • Hadrian's Villa (Villa Adriana; near Tivoli): Hadrian's Villa slumbered in rural obscurity until the 1500s, when Renaissance popes ordered its excavation. Only then was the scale of this enormous and beautiful villa from A.D. 134 appreciated. Its builder, Hadrian, who had visited almost every part of his empire, wanted to incorporate the wonders of the world into one building site — and he succeeded.
  • Ostia Antica (near Rome): During the height of the Roman Empire, Ostia ("mouth" in Latin) was the harbor town set at the point where the Tiber flowed into the sea. As Rome declined, so did Ostia; by the early Middle Ages, the town had almost disappeared, its population decimated by malaria. In the early 1900s, archaeologists excavated the ruins of hundreds of buildings, many of which you can view.
  • Fori Imperiali: Lining both sides of the Via dei Fori Imperiali are the Imperial Forums, launched by Julius Caesar in 54 B.C. that includes the Temple of Venus Genetrix, dedicated to the goddess of love from whom Caesar immodestly claimed descent. On the east side are the ruins of the forums constructed by the emperors Nerva, Augustus, and Trajan. On the west side, closer to the Colosseum, you can see marble maps, ordered made by Mussolini, charting the vast outreaches of the Roman Empire in its heyday.
  • Trajan's Market: Adjoining the Imperial Forum, Trajan's Market in its heyday was one of the wonders of the classical world. Imagine it in all its glory when its 150 shops sold the rarest of treasures from the far reaches of the Roman Empire. The Emperor Trajan ordered his architect, Apollodorus of Damascus, to construct this avant-garde complex in the early 2nd century A.D. The market today only vaguely suggests what it used to be when it sold silks, spices, fresh fish, fruit, and flowers, a spectacle to behold.
  • Terme di Caracalla: These baths lasted for 3 centuries until invading Goths destroyed the plumbing. They were ordered built by the Emperor Caracalla in A.D. 217. Back then, a noble Roman could spend the entire day at the baths, enjoying various pleasures including rubdowns with scented cloths. In its heyday, the baths also had art galleries, beautiful gardens, a big library, and even today's equivalent of a gym. One will have to imagine the magnificence of these baths before the Farnese family carted off their marble decorations in the 16th century.

Nero's Golden House ★★★
 After the Great Fire of a.d. 64, charismatic, despotic Emperor Nero staged a land grab to facilitate construction of his Domus Aurea, or Golden House, a massive, gilded villa complex covering all or parts of the Palatine, Esquiline, and Caelian hills and displaying a level of ostentation and excessiveness unheard of even among past emperors. After his death by noble suicide in a.d. 68, a campaign to erase all traces of Nero from the imperial city ensured that the palace was stripped of its gold, marble, jewels, mosaics, and statuary, then intentionally buried under millions of tons of rubble. It remained buried until the Renaissance, when young artists, including Raphael, descended into its “grottos” (actually the vaulted ceilings) to study the fanciful frescoes—the term grotesque (grotto-esque) was coined here. Later excavations, both haphazard and scientific, revealed the scale and richness of the villa, but also subjected it to catastrophic moisture damage. After a years-long closure for restoration and re-stabilization, the Domus Aurea is once again open for tours—but only if you time your trip well and plan ahead. Guided tours (16€) of the scaffolded underground site (hardhats required) are offered on Saturdays and Sundays only, and with advance reservations. The tour includes a spectacular virtual reality experience that in itself is worth the visit.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.