Rome was born, about 3,000 years ago, here — along the Tiber River. This was as far upstream as boats could sail, and the first place the river could be crossed by bridge.

As a center of river trade, Rome connected the interior of the Italian peninsula with the Mediterranean. The riverbank would have been bustling in ancient times. Imagine: busy docks, ramshackle boats, water mills, and platforms for fishing.

Until modern times, Rome's river was part of its economy. Then, in the 1870s, in order to protect the city from flooding, the Romans walled off the Tiber. They built these tall, anonymous embankments that continue to isolate the river from the city to this day. While Rome was born on the Tiber, today the town seems to ignore its river.

But the city's graceful bridges connect thriving neighborhoods. Just over the Tiber from here is one of Rome's most colorful districts.

Trastevere is the place to immerse yourself in the crustier side of Rome. The name, Trastevere, actually means "across the Tiber River."

Wandering here offers a chance to hone your senses, to see Rome more intimately. You'll discover a world of artisans who've found their niche and love it. The people here — "Trasteverini" — are proud. Old-timers once bragged of never setting foot on the opposite side of the Tiber. As we explore and observe, the big city seems worlds away.

For maximum Trastevere fun and insight, I'm joined by my friend and Roman tour guide, Francesca Caruso.

Rick: Especially here in Trastevere you get this sense of the many layers of Rome…
Francesca: Certainly. That is really the key to understanding Rome. This city, with almost 3,000 years of history, was never abandoned. So people have just built on top of and around what was already there.
Rick: Like a layer cake, isn't it?

Rick: Boy, there's a beautiful roof garden.
Francesca: Yeah, most of us in Rome live in apartments, so no gardens, no backyard…so we all dream of the attico con terrazzo.
Rick: Attico con terrazzo, an attic with a terrace.
Francesca: Yes, so the skyline of Rome is full of these little jungles on the rooftops.
Rick: Everything's so intimate, it's like we're walking through somebody's laundry room.
Francesca: Well, we've always lived so very close together here — sharing space is really not a problem. We don't even have the word for "privacy" in Italian. We use the English word instead; we simply roll the R so we say "privacy." [rolls the R]
Rick: Privacy [rolls the R}. I know one more Italian word now.

Rick: So, why are so many of the oldest churches in Rome on this side of the river?
Francesca: Because Trastevere was the neighborhood of foreigners, often Christian, who brought their faith with them. Through the whole period of the persecutions they could not build churches. So, mass would be celebrated in the homes of wealthy converts who offered their homes for mass.
Rick: So, this is one of those kind of churches.
Francesca: Yes, it was the house of Cecilia, and in later times they built a church dedicated to her.
Rick: And today the name of the church?
Francesca: Is Santa Cecilia.
Rick: Now, what happened to St. Cecilia?
Francesca: St. Cecilia and her husband were killed because of their faith. The Romans tried to steam her to death for three days in her own home, and after that they beheaded her.
Rick: This is a beautiful statue. It's just peaceful.
Francesca: Yes; it's very quiet. There's something very tender about it, and also very sad about a young woman who was killed so brutally for her faith.

The concept of a piazza serving as a community center goes back to ancient times. Piazza Santa Maria in Trastevere is the heart of this neighborhood. With its broad and inviting steps, the fountain was actually designed to be a kind of neighborhood "sofa."

Rick: A great part of exploring a neighborhood is just sitting on the main square.
Francesca: Yeah, I think it's really in our DNA. We've been living in our piazzas as common living rooms since ancient Roman times. It's always been this way, and let's hope it will always be this way in the future, too.

And, as usual, the district's main church fronts the main square. The Church of Santa Maria in Trastevere is also one of Rome's oldest and most beloved churches.

Like Cecilia's church, it's built on the site of a third-century home where early Christians worshipped illegally. And, like the city itself, it's been a work in progress, rebuilt continuously over the centuries.

The portico is decorated with ancient fragments filled with early Christian symbolism — the anchor, birds, people with hands up praying as evangelical Christians do today. Many of these stones were originally lids to burial niches from catacombs.

Stepping inside takes you back centuries. The granite columns were scavenged from ancient Roman buildings. The church feels like an ancient hall of justice. That's because early churches adopted the pre-Christian basilica floor plan — a rectangular space divided by rows of columns.

These mosaics are early medieval — well over a thousand years old. They're rich in symbolism: Mary is given a high stature. She's at the throne with Jesus in heaven. He has his arm around his mother, as if introducing her to us. Locals claim this is the first church dedicated to the Virgin Mary.

I never leave without checking in with St. Anthony, who hangs out in the back. He's a favorite of the poor, and is inundated with prayer requests on scraps of paper.