There are enough interesting things to see and do in Venice alone (not to mention the surrounding region) to fill weeks and even months of exploring. Assuming you don't have the luxury of that much time, you can use the plan below as an introduction to the world's most beautiful city.
Start with a morning cruise along the Grand Canal from Piazzale Roma to San Zaccaria. You'll see Piazza San Marco for the first time from the water, as travelers before you have for hundreds of years. Spend the morning visiting the Basilica and Palazzo Ducale, allowing time to climb the Campanile. After lunch, take Salizzada San Moisè and Calle Larga XXII Marzo -- lined with fashionable shops -- to reach the traghetto (gondola ferry) in Campo Santa Maria del Giglio. Once across the Grand Canal, bear left and walk to the baroque Chiesa della Madonna della Salute, with several paintings by Titian. The Punta della Dogana, to the right as you come out of the church, opens to one of the best panoramas in town. Head for the Peggy Guggenheim Collection, home of first-rate 20th-century art, and then stretch your legs on the Zattere promenade while having a gelato.
On day two, start early to beat the crowds at the Rialto Bridge and market. Don't miss the lively pescheria, where fish have been sold for more than 1,000 years. Follow the main drag to Campo San Polo and the Chiesa dei Frari, with two important works by Titian. Visit the Scuola Grande di San Rocco, famous for a series of more than 50 paintings by Tintoretto -- Venice's answer to the Sistine Chapel. After lunch, jump into 18th-century Venice at Ca' Rezzonico. Finish your day with a visit to the Gallerie dell'Accademia, with masterpieces of Western painting dating from the 14th to 19th century.
Start day three by exploring the sestiere of Castello. (On a clear morning, consider a stop first on the Isola di San Giorgio, with breathtaking views of the lagoon and the city. From Piazza San Marco, go to the church of San Zaccaria, with a famous altarpiece by Giovanni Bellini. Then visit the Greek church of San Giorgio dei Greci, lined with Byzantine icons. Time your walk to hit the Scuola di San Giorgio degli Schiavoni before it closes at midday. Take a glance at the graceful Santa Maria Formosa, then follow Calle del Paradiso via Campo Santa Marina toward a miracle born of marble, Santa Maria dei Miracoli. After a late lunch, visit Campo Santi Giovanni e Paolo and its Gothic abbey; then take Barbaria delle Tole to the Campo dell'Arsenale. Take vaporetto Line 82 from the Giardini della Biennale to the Giudecca, where you can have dinner, or return to Piazza San Marco along the Riva degli Schiavoni, particularly beautiful at sunset.
On your final morning, take a guided tour of the Jewish Ghetto. Board vaporetto Line 42 (Ponte delle Guglie landing) by 11 AM, cruising to the islands of the lagoon: Murano and its glass museum, where you should stop for lunch; Burano and its lace museum, where you should have a merenda (afternoon tea) with the local cookies called buranelli; and romantic Torcello, wrapped in the mists of the lagoon.
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