Built in 12 BC, the Pyramid of Caius Cestius was a tomb for Gaius Cestius (a wealthy magistrate) and was also a landmark for travelers along the Via Ostiensis and the River Tiber. While you're in the neighborhood, the Protestant Cemetery and Porta San Paolo are just around the corner and both are underrated gems.

Pyramid of Caius Cestius

These catacombs date back to the third century AD., and roughly 500,000 people are buried here, including countless martyrs and 16 popes. With guided tours and lots to see, this is another underrated point of interest in Rome that should be on the itinerary for anyone who loves history with a dash of dark tourism.

Ancient Ruins of Ostia Antica

Rome is home to several underground networks, with the third century AD catacombs of Saint Callixutus being the largest — roughly 500,000 people are buried there, including countless martyrs and 16 popes. Guided tours will take you around the 90 acres, with 12-mile-long galleries and multiple levels.

Catacombs of Saint Callixtus

Built in the mid-1600s, this breathtaking palace in Rome is a beautiful mansion and museum. The private art collection is the largest in all of Rome, which was originally started in 1644. Gifted by Pope Clement XII to the Doria family in the 18th century, Palazzo Doria Pamphilj is a great addition to your itinerary.

Palazzo Doria Pamphilj

At the Church of Santa Maria del Priorato, once owned by the military order, Knights of Malta, a door with a special keyhole and a private garden awaits. Visitors can peer through a medieval-looking lock — and the keyhole lines up almost perfectly with a well-manicured shrub and gives viewers a clear vantage point of the dome of St Peter's Basilica.

Knights of Malta Keyhole