TRAVELER @ nationalgeographic.com

In Traveler magazine’s April issue, writer Taras Grescoe scouts out 12 great hotels in Rome with rooms for under $135 U.S. Here, Grescoe, author of Sacré Blues: An Unsentimental Journey Through Quebec, teams with Rome-based Michael Brouse and Sari Gilbert, co-authors of the National Geographic Traveler Rome, to tell you how to explore the city.

Many say it’s best to explore Rome on foot. But to see the most during a short visit, tour by scooter. “You can cram a lot into the day and get close to sites,” says Gilbert. Rent one at Trevi Tourist Center (Via dei Lucchesi 32). Five-hour rentals are $18 U.S.

There are more than 900 churches in Rome. “No matter how obscure or small, every church has something to entice an art historian or neophyte,” says Brouse. “I stop into them often—and I’m an atheist.”

The skeletal remains of 4,000 Capuchin monks, arranged in hearts and rosettes underneath the Santa Maria della Concezione (Via Veneto 27), “make the people who stacked the bones in Paris’s catacombs look like amateurs,” says Grescoe.

What appears to be a dome at the Sant’Ignazio di Loyola (Piazza di Sant’Ignazio) is actually a trompe l’oeil, “The Entry of St. Ignatius into Paradise,” by 17th-century painter Andrea del Pozzo. Stand on the marble disk in the middle of the floor and look up. “From here the dome looks almost real,” says Brouse.

In the Santa Maria della Pace (Vicolo dell’ Arco della Pace 5) is Italian Renaissance painter Raffaello Sanzio’s depiction of a sibyl, a prophetess in Greek legend and literature. With this fresco, Sanzio pays homage to Michelangelo’s artistic style by painting robust, muscular figures instead of his characteristically lithe, graceful forms.

Stop by Janiculum Park on the weekend to see the 300-year-old Pulcinella (the original Punch and Judy Show). The mischievous Punch, a hunchback puppet with a hooked nose, first appeared in Italy’s 17th-century Commedia dell’Arte troupes. The follies you see today—which were inspired by Punch’s 17th-century escapades—also feature Judy, his feisty puppet wife.

Start at the Scalinata Trinità dei Monti (Piazza di Spagna), a cascading 1720s staircase that overlooks a tight grid of streets—Vie Borgognona, Veneto, Condotti, and Frattina—where Armani and Versace, among others, sell designer clothes. (For a map, click here.)

On Sunday, visit the Porta Portese flea market (on streets between Porta Portese, Ponte Testaccio and Viale di Trastevere), for authentic (and faux) paintings, antique furniture, vintage clothes, hand-painted china, and more. To beat the crowds, arrive when it opens at 6 a.m.

Shop at the open-air market in Campo dei Fiori for fresh fruit and vegetables (open until 1 p.m. Monday through Saturday). For goat cheese, prosciutto, and more than 60 kinds of fine Italian wine, shop at Volpetti (Via Marmorata, 47), a gourmet specialty shop.

Order a molto, molto lungo coffee, so the tiny demitasse cup is almost full, and a hot, chocolate-filled brioche at De Marzio, across the street from the basilica of Santa Maria in Trastevere. $1.60 U.S. for brioche and coffee.

For espresso with just the right touch of cream, and a hot cornetto (a buttery Italian croissant), or maritozzo (a horn-shaped pastry filled with cream), stop by La Tazza d’Oro (Via degli Orfani 84/86). $1.60 U.S. for espresso and pastry.

La Tana de Noantri (Via della Paglia 1/2/3) in bohemian Trastevere is “unpretentious and shows that good Italian eating doesn’t necessarily involve waiters offering fresh ground pepper and a massive bill,” says Grescoe. Try the gorgonzola and tomato pizza or the smoked-salmon ravioli. $42 U.S. for a three-course meal, including tax, tip, and a nonalcoholic drink.

After visiting the church of San Lorenzo in Lucina—where pieces of Augustus’s great sundial are buried—go to Ciampini (Piazza di San Lorenzo) for tramezzini, finger sandwiches with ham and cheese. $2.61 U.S. for two tramezzini.

In Campo dei Fiori, behind the market’s flower stands, is Il Forno di Campo dei Fiori (at the corner of Campo dei Fiori and Vicolo dei Cappellari). “There’s always a crowd inside,” says Brouse. “But the pizza bianca is worth the wait.” $2.50 U.S. for a single serving of pizza bianca.