Start: Via della Conciliazione (Piazza Pia)

Finish: Galleria Doria Pamphilj

Time: 4 hours, not counting a tour of the Castel Sant'Angelo and visits to the Palazzo Spada and the Galleria Doria Pamphilj

Best Times: Early and midmornings

Worst Times: After dark

The threads that unify this tour are the grandiose tastes of Rome's Renaissance popes and the meandering Tiber River that has transported building supplies, armies, pilfered treasures from other parts of Europe, and such famous personages as Cleopatra and Mussolini into Rome. Slower and less powerful than many of Italy's other rivers (such as the mighty Po, which irrigates the fertile plains of Lombardy and the north), the Tiber varies from a sluggish ribbon of sediment-filled water only 1.2m deep (4 ft.) to a 6m-deep (20-ft.) torrent capable of flooding the banks that contain it.

The last severe flood to destroy Roman buildings occurred in 1870. Since then, civic planners have built mounded barricades high above its winding banks, a development that has diminished the river's visual appeal. The high embankments, as well as the roaring traffic arteries that parallel them, obscure views of the water along most of the river's trajectory through Rome. In any event, the waters of the Tiber are so polluted that many modern Romans consider their concealment something of a plus.

Begin your tour at Piazza Pia. (Don't confuse Piazza Pia with nearby Piazza Pio XII.) Piazza Pia is the easternmost end of Rome's most sterile and impersonal boulevard. Start at:

1. Via della Conciliazione

Construction of this boulevard, conceived by Mussolini as a monumental preface to the faraway dome of St. Peter's Basilica, required the demolition of a series of medieval neighborhoods between 1936 and 1950, rendering it without challenge the most disliked avenue in Rome.

Walk east toward the massive and ancient walls of the:

2. Castel Sant'Angelo

Originally built by Emperor Hadrian in A.D. 135 as one of the most impressive mausoleums in the ancient world, it was adapted for use as a fortress, a treasure vault, and a pleasure palace for the Renaissance popes. Visit its interior, noting the presence near the entrance of architectural models showing the castle at various periods of its history. Note the building's plan (a circular tower set atop a square foundation) and the dry moats (used today for impromptu soccer games by neighborhood kids), which long ago were the despair of many an invading army.

After your visit, walk south across one of the most ancient bridges in Rome:

3. Ponte Sant'Angelo

The trio of arches in the river's center is basically unchanged since the bridge was built around A.D. 135; the arches that abut the river's embankments were added late in the 19th century as part of a flood-control program. On December 19, 1450, so many pilgrims gathered on this bridge (which at the time was lined with wooden buildings) that about 200 of them were crushed to death. Today the bridge is reserved exclusively for pedestrians; vehicular traffic was banned in the 1960s.

On the southern end of the bridge is the site of one of the most famous executions of the Renaissance:

4. Piazza Sant'Angelo

Here, in 1599, Beatrice Cenci and several members of her family were beheaded on the orders of Pope Clement VIII for plotting the murder of their very rich and very brutal father. Their tale later inspired a tragedy by Shelley and a novel by 19th-century Italian politician Francesco Guerrazzi.

From the square, cut southwest for 2 blocks along Via Paola (crossing the busy traffic of Corso Vittorio Emanuele in the process) onto:

5. Via Giulia

Laid out during the reign of Pope Julius II (1503-13), Via Giulia and its straight edges were one of Renaissance Rome's earliest examples of urban planning. Designed to facilitate access to the Vatican, it was the widest, straightest, and longest city street in Rome at the time of its construction and was bordered by the 16th-century homes of such artists as Raphael, Cellini, and Borromini, and the architect Sangallo. Today the street is lined with some of the most spectacular antiques stores in Rome.

At the terminus of Via Paola, the first building on Via Giulia you're likely to see is the soaring dome of the:

6. Florentine Church (Chiesa di San Giovanni dei Fiorentini)

This is the premier symbol of the city of Florence in papal Rome. Its design is the result of endless squabbling among such artistic rivals as Sansovino, Sangallo, and Maderno, each of whom added embellishments of his own. Michelangelo also submitted a design for the church, although his drawing did not prevail during the initial competition. Most of the building was completed during the 1620s, and Lorenzo Corsini added the facade during the 1700s.

Now walk in a southeasterly direction along Via Giulia, making special note of houses at no. 82 (built in the 1400s, it was offered by Pope Julius II to the Florentine community), no. 85 (the land it sits on was once owned by Raphael), and no. 79 (built in 1536 by the architect Sangallo as his private home, it was later snapped up by a relative of Cosimo de' Medici).

In less than 3 short blocks, on the northwest corner of Vicolo del Cefalo, rises the symmetrical bulk of the:

7. Palazzo Sacchetti

Completed by Vasari in the mid-1500s, it was built for the Sacchetti family, a Florence-based clan of bankers and merchants who moved to Rome after they lost an epic power struggle with the Medicis.

Continue walking south along Via Giulia. On your right rises the baroque facade of the unpretentious:

8. Chiesa di San Biagio

Although its front was added in the early 1700s, it's actually one of the oldest churches in Rome, rebuilt from an even earlier model dating to around 1070. The property of an Armenian Christian sect based in Venice, the church is named after an early Christian martyr (St. Biagio), a portion of whose throat is included among the sacred objects inside.

Walk another short block south along Via Giulia. Between Via del Gonfalone and Vicolo della Scimia are the barred windows of what was originally built early in the 19th century as a:

9. Prison for Minors

This, along with another nearby building (at Via Giulia 52, a few blocks to the south, which was built during the mid-1600s), incarcerated juvenile delinquents, political prisoners, debtors, common rogues, and innocent victims of circumstance for almost a hundred years. During its Industrial Revolution heyday, armed guards supervised all comings and goings along this section of Via Giulia.

Turn right onto Vicolo della Scimia and descend toward the Tiber. On your left, at no. 18, is a building used since the early 1500s as a guildhall for the flag-bearers of Rome, the:

10. Oratorio del Gonfalone

The guild of flag-bearers had, by the time this building was constructed, evolved into a charitable organization of concerned citizens and a rather posh social and religious fraternity. The frescoes inside were painted in 1573 by Zuccari. Restored during the early 1980s, they now form a backdrop for concerts held inside. The building is usually open Monday through Friday from 10am to 4pm -- guided visits only. Make a reservation in advance online (follow the link).

Walk to the very end of Vicolo della Scimmia and make a hard left onto Vicolo Prigioni, which will eventually lead back to Via Giulia. At this point, as you continue to walk south along Via Giulia, you'll notice a swath of trees and a curious absence of buildings flanking the corner of Via Moretta. In 1940, Mussolini ordered the demolition of most of the buildings along Via Moretta for the construction of a triumphal boulevard running from east to west. His intention -- which was never fulfilled -- was to link together the nearby Ponte Mazzini with Corso Vittorio Emanuele. One building that suffered was the building near the corner with a baroque facade, the:

11. Chiesa di San Filippo Neri

Originally funded during the early 1600s by a wealthy but ailing benefactor in hopes of curing his gout, the church retains only its facade -- the rest of the building was demolished. Where choirs once sang and candles burned during Mass, there is now a market for fruit and vegetables.

About another block to the south, on your right, rises the bulk of the:

12. Chiesa dello Spirito Santo del Napolitani

Once one of the headquarters of the Neapolitan community in Rome, the version you see today is a product of a rebuilding during the 1700s, although parts of the foundation were originally constructed during the 1300s.

Slightly farther south, at Via Giulia 146, rises the:

13. Palazzo Ricci

This is one of the many aristocratic villas that once flanked this historic street. For a better view of its exterior frescoes, turn left from Via Giulia into Piazza Ricci to admire this building from the rear.

Returning to Via Giulia, walk south for a block, and then turn right onto Via Barchetta. At the corner of Via di San Eligio, notice the:

14. Chiesa di San Eligio degli Orefici

According to popular belief, this church was designed by Raphael in 1516. Completed about 60 years later, it was dedicated to (and funded by) the city's gold- and silversmiths.

Return to Via Giulia and notice, near its terminus at Via Giukua 16, the:

15. Palazzo Varese

This structure was built as an aristocratic residence in the Tuscan style.

Nearby, at Via Giulia 151, is the:

16. Palazzo of the Spanish Establishment

Constructed in anticipation of the 1862 visit of Queen Elizabeth II of Spain, for the occasion of her charitable visit to Rome, it was designed by Antonio Sarti.

Continue walking south along Via Giulia, past the faded grandeur of at least another half-dozen palazzi. These will include the Palazzo Cisterno (from about 1560), at no. 163; Palazzo Baldoca/Muccioli/Rodd (about 1700), at no. 167; and Palazzo Falconieri (about 1510), at no. 1.

Opposite the corner of Via dei Farnesi rise the walls of one of the most macabre buildings in Rome, the church of:

17. Santa Maria dell'Orazione e Morte

Built around 1575 and reconstructed about 160 years later, it was the property of an order of monks whose job it was to collect and bury the unclaimed bodies of the indigent. Notice the depictions of skulls decorating the church's facade. During the Renaissance, underground chambers lined with bodies led from the church to the Tiber, where barges carried the corpses away. Although these vaults are not open to the public, the church's interior decoration carries multiple reminders of the omnipresence of death.

After exiting the church, notice the covered passageway arching over Via Giulia. Built in 1603 and designed by Michelangelo, it connected the church with the:

18. Palazzo Farnese

The rear side of the palazzo rises to your left, with the Tiber and a series of then-opulent gardens and villas that no longer exist. The Palazzo Farnese was designed by Sangallo and Michelangelo, among others, and has housed dignitaries ranging from Pope Paul III to Queen Christina of Sweden. Today the French Embassy, it's closed to the public. For the best view of the building, cut west from Via Giulia along any of the narrow streets (Via Mascherone or Via dei Farnesi will do nicely) to reach Piazza Farnese.

To the southwest is a satellite square, Piazza Quercia, at the southern corner of which rises the even more spectacular exterior of the:

19. Palazzo Spada

Built around 1550 for Cardinal Gerolamo Capo di Ferro, its ornate facade is stuccoed in high relief in the mannerist style. Although the staterooms are closed to the public, the courtyard and several galleries are open.

From here, walk 2 blocks north along either Vicolo del Grotte or Via Balestrari until you reach one of the most famous squares of Renaissance Rome:

20. Piazza Campo de' Fiori

During the 1500s, this square was the geographic and cultural center of secular Rome, with inns and the occasional burning at the stake of religious heretics. Today the campo hosts a morning open-air food market every day except Sunday.

After your visit, continue to walk north for 3 meandering blocks along the narrow confines of Via Baullari to:

21. Piazza San Pantaleo/Piazza di Pasquino

Its edges are the site of both the Palazzo Massimo (to the east) and the Palazzo Braschi (Museo di Roma) to the north. The Palazzo Massimo (currently home to, among other things, the Rome campus of Cornell University) was begun as a private home in 1532 and designed with an unusual curved facade that corresponded to the narrow confines of the street. Regrettably, because it's open to the public only 1 day a year (Mar 17), it's viewed as a rather odd curiosity from the Renaissance by most passersby. More accessible is the Palazzo Braschi, built during the late 1700s by Pope Pius VI, né Giovanni Angelo Braschi, for his nephews. Severe and somewhat drab, it was the last palace ever constructed in Rome by a pope. Since 1952, it has contained the exhibits of the Museo di Roma, a poorly funded entity whose visiting hours and future are uncertain.

Continue walking north for 2 blocks until you reach the southernmost entrance of the most thrilling square in Italy:

22. Piazza Navona

Originally laid out in A.D. 86 as a stadium by Emperor Domitian, stripped of its marble in the 4th century by Constantine, and then embellished during the Renaissance into the lavish baroque form you see today, Piazza Navona has witnessed as much pageantry and heraldic splendor as any site in Rome. The fact that it's reserved exclusively for pedestrians adds enormously to its charm but makes parking in the surrounding neighborhood almost impossible.

23. Take A Break

Established in 1882, Tre Scalini, Piazza Navona 30 (tel. 06-6879148; www.ristorante-3scalini.com), is the most famous cafe on the square, although it is too tourist ridden for most tastes. Literally hundreds of people go here every day to sample the tartufo (ice cream disguised with a coating of bittersweet chocolate, cherries, and whipped cream). There are simpler versions of gelato as well.

After you've perked yourself up with sugar or caffeine or both, head for the piazza's northwestern corner, adjacent to the startling group of heroic fountains at the square's northern edge, and exit onto Via di Lorenesi. Walk westward for 2 crooked blocks, forking to the left onto Via Parione until you reach the edge of one of the district's most charming churches:

24. Santa Maria della Pace

According to legend, blood flowed from a statue of the Virgin above the altar after someone threw a pebble at it. This legend motivated Pope Sixtus IV to rebuild the church in the 1500s on the foundations of an even older sanctuary. For generations after that, its curved porticos, cupola atop an octagonal base, and frescoes by Raphael helped make it one of the most fashionable churches for aristocrats residing in the surrounding palazzos.

After admiring the subtle, counterbalancing curves of the church, retrace your steps to the welcoming confines of Piazza Navona, and then exit from it at its northernmost (narrow) end. Walk across the broad expanse of Via Zanardelli to its northern edge, and then head east for 2 blocks to Piazza San Agostino, on whose northern flank rises the:

25. Chiesa di San Agostino

Built between 1479 and 1483 and originally commissioned by the archbishop of Rouen, France, it was one of the first churches erected in Rome during the Renaissance. Its interior was altered and redecorated in the 1700s and 1800s. A painting by Caravaggio, Madonna of the Pilgrims (1605), hangs over the first altar on the left as you enter.

After your visit, continue walking east along Via Zanardelli, turning south in about a block onto Via della Scrofe. Be alert to the fact that this street changes its name in rapid order to Largo Toniolo and Via Dogana. Regardless of how it's marked, walk for about 2 blocks south. On the right, you'll see a particularly charming church, the:

26. Chiesa di San Luigi dei Francesi

This has functioned as the national church of France in Rome since 1589. Subtly carved into its facade is a stone salamander, the symbol of the Renaissance French monarch François I. Inside is a noteworthy series of frescoes by Caravaggio, The Martyrdom of St. Matthew.

Continue walking south for less than a block along Via Dogana, and then turn left for a 2-block stroll along the Salita dei Crescenzi. Suddenly, at Piazza della Rotonda, there will emerge a sweeping view of one of our favorite buildings in all of Europe:

27. The Pantheon

Rebuilt by Hadrian around A.D. 125, it's the best-preserved ancient monument in Rome, a remarkable testimony to the skill of ancient masons, whose (partial) use of granite helped ensure the building's longevity. Originally dedicated to all the gods, it was transformed into a church (Santa Maria ad Martyres) by Pope Boniface IV in A.D. 609. Many archaeologists find the building's massive, slightly battered dignity thrilling. Its flattened dome is the widest in the world, exceeding the width of the dome atop St. Peter's by about .6m (2 ft.).

28. Take A Break

Di Rienzo, Piazza della Rotonda 9 (tel. 06-6869097), is a great cafe. Here you can sit at a table enjoying a pick-me-up while you view not only one of the world's premier ancient monuments, but also the lively crowd of people who come and go on this square, one of the most interesting in Rome. Open daily from 7am to 3am.

After your coffee, walk southward along the eastern flank (Via Minerva) of the ancient building. That will eventually lead you to Piazza di Minerva. On the square's eastern edge rises the massive and severe bulk of a site that's been holy for more than 3,000 years:

29. Chiesa di Santa Maria Sopra Minerva

Beginning in 1280, early Christian leaders ordained that the foundation of an already ancient temple dedicated to Minerva (goddess of wisdom) be reused as the base for Rome's only Gothic church. Unfortunately, architectural changes and redecorations during the 1500s and the 1900s weren't exactly improvements. Despite that, the awe-inspiring collection of medieval and Renaissance tombs inside creates an atmosphere that's something akin to a religious museum.

After your visit, exit Piazza di Minerva from the square's easternmost edge, following Via del Gesù in a path that proceeds eastward, and then meanders to the south. Continue walking southward until you eventually cross over the roaring traffic of Corso Vittorio Emanuele II/Via del Plebiscito. On the southern side of that busy avenue, you'll see a church that for about a century after the Protestant Reformation was one of the most influential in Europe, the:

30. Chiesa del Gesù

Built between 1568 and 1584 with donations from a Farnese cardinal, this was the most powerful church in the Jesuit order for several centuries. Conceived as a bulwark against the perceived menace of the Protestant Reformation, it's sober, monumental, and historically very important to the history of the Catholic Counter-Reformation. The sheathing of yellow marble that covers part of the interior was added during the 1800s.

After your visit, cross back over Via del Plebiscito, walk eastward for 2 blocks, and turn left (north) onto Via de Gatta. Pass through the first piazza (Piazza Grazioli), and then continue northward to Piazza del Collegi Romano, site of the entrance to one of Rome's best-stocked museums, the:

31. Galleria Doria Pamphilj

See the full listing for information on this wonderful museum.

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.