Pisa is divided into 4 historical quarters. There is much more than the Leaning Tower in the city and several different walking itineraries are available.

 
The leaning tower.The Piazza dei Miracoli or Field of Miracles is to the north of central Pisa. It's an UNESCO World Heritage site and contains the city's most famous sights:
Torre Pendente (Leaning Tower) [3] The structure was originally conceived as the cathedral's bell tower. Construction began in 1173 and the tower started leaning soon afterwards due to subsidence of the ground underneath its base. A project to keep the tower from leaning more and tipping over finally reached a successful conclusion in 2001, and the tower is again open to those wishing to climb it. Climbing the tower requires a reservation-based ticket for 15 Euro. Expect 45 minutes to 2 hours wait, but there is a lot to see while you wait. It is better if you buy tickets online for ?17 well in advance at [4]. Warning, the tickets are non-exchangeable, effectively non-refundable, and only good for the Torre, so they're a bit of a risk to purchase in advance. Make the effort to climb, though, and you'll be rewarded by the view. Curiosity: the famous Pisa leaning tower is not the only one, due of the marshy land that they are built on, there are other 2 towers in Pisa: the Bell Tower of San Nicola Church, near the banks of Arno and the Bell Tower of San Michele of Scalzi Church.[5]
Duomo di Pisa, (Cathedral of Pisa) the splendid cathedral, contains artwork by Giambologna, Della Robbia, and other major artists. Fine Romanesque style with double aisles and a cupola, a huge apse mosaic partly by Cimabue, and a fine pulpit by Giovanni Pisano in late Gothic / early Renaissance style.
Battistero (Baptistry) large round Romanesque dome with many sculptured decorations and a fine view up top; climb this if you want a great view with the Leaning Tower visible in your photos. Arabic-style pavement, pulpit by Nicola Pisano (father of Giovanni), and fine octagonal font. At regular intervals, the ticket-checker-guard at the entrance comes into the baptistery and gives an audio-treat of echo-effect. The guard shouts out few sounds which when echoed sound like pure beautiful music. Do not miss it. You can also cast your inhibitions to the wind, stand by the wall, and sing long notes that turn into chords by yourself, as the echoes go round and round the dome of the building.
Campo Santo Monumentale (Cemetery) a huge cemetery building with lots of interesting art, including a collection of ancient Roman sarcophagi and splendid medieval frescoes by the "Master of the Triumph of Death".
Museo del Opera del Duomo has sculptures and paintings formerly preserved in the Cathedral and the cemetery. Some of the more unusual are bronze griffins from Syria captured by the Crusaders.
Museo delle Sinopie Skipped over by many visitors, this museum is a treat for art lovers. After WWII many of the surviving murals and pieces of murals from Pisa's Campo Santo were detached from the walls to try to preserve them. It was unexpectedly discovered that the artist sketches underneath survived. These were moved to this museum.
Piazza dei Cavalieri a small town square with many historical buildings that hosted the political powers of the city in the middle ages and Renaissance, but most of them are not accessible to tourists, as they are now property of the University of Pisa or Scuola Normale Superiore (a prestigious elitary school).
Palazzo della Carovana, the main Scuola Normale Superiore building, with an elaborate façade, by the important Italian Renaissance artist and architect Giorgio Vasari - who is also said to be the first historian of art.
Palazzo dell'Orologio (Clock Palace), a XIV century building that has replaced the Torre della Fame (tower of hunger), where the Conte Ugolino della Gherardesca was imprisoned and left to die of hunger with his sons, as cited in the Dante's Divina Commedia
Chiesa di Santo Stefano, designed by Giorgio Vasari in the XVI century for the Ordine dei Cavalieri di Santo Stefano (Order of Chivalry of Saint Stephan), a chivalry order founded to fight piracy in 1561.
other historical buildings include the Church of San Rocco, the Rectory, Palazzo Carovana and Palazzo dei Dodici.
 
The Museo di San Matteo (St Matthew Musem)Lungarno Mediceo and Lungarno Pacinotti on the north side of Arno river, Lungarno Galilei and Lungarno Gambacorti on the south side: these riverside streets give a distinctive character to Pisa, especially at night when the lamplight reflects on the Arno river. Along the Lungarni stands intresting places like:
Piazza Garibaldi and Piazza XX Settembre, two opposing town square, one at each end of Ponte di Mezzo (middle bridge), and are considered the center of the city. From Piazza Garibaldi starts Borgo Stretto, an old street with lots of shops that, together with Corso Italia starting in the opposite direction from Piazza XX Settembre, create a pedestrian area (interrupted only by the bridge) that is considered the center of the city. In Piazza XX Settembre you can find the Logge dei Banchi, a building created to host textile market in 1600, and the town hall, in the Palazzo del Comune.
Museo di San Matteo, on Lungarno Mediceo, a small history and art museum, but one of the biggest for Tuscan Renaissance art, hosted in the rooms of the San Matteo monastery. Address: Piazza San Matteo, 1, lungarno Mediceo Tel. +39 050 541865 begin_of_the_skype_highlighting              +39 050 541865      end_of_the_skype_highlighting
Santo Sepolcro, on Lungarno Galilei, a Romanesque octagonal church with conical spire by Diotisalvi, who also built the baptistry - a Templar church, striking and forceful. Usually is not open to the public.
Ussero Café founded on 1775, lungarno Pacinotti 27, [6]. A monument to Italian culture in the 1400's Palazzo Agostini, on Lungarno. In 1839, it was seat of the meetings of the first Italian Congress of Scientists.
Santa Maria della Spina, on Lungarno Gambacorti, a very small Gothic church built in 1230 to house a thorn from Jesus's crown, it's considered one of the best expressions of Italian gothic. It is so small it moved from the river of the Arno, in 1800, to a place some meters above, one stone at time, to protect it from flooding. Usually it's not open to the public.
Giardino Scotto, on Lungarno Fibonacci at the end of Lungarno Galilei, is a fortress converted to a public park which opens in summer for open air cinema, music shows and other events.
La Cittadella, at the end of Lungarno Simonelli, is a fortress built to guard the access by the river Arno and the shipyard in the middle age, when the sea was closer to the city.
University botanical garden, via Luca Ghini 5, is the first university botanical garden of Europe, created by the will of Cosimo de Medici in 1544. It is open weekday mornings and is free to the public.
Fine Romanesque churches - San Paolo a Ripa d'Arno, San Michele in Borgo, San Paolo with a sculpture gallery inside, Sant'Andrea - not all are open every day; double-check the hours if you want to visit.
Tuttomondo, Keith Haring mural [7]. Keith Haring visited Pisa and fell in love with the town, so he decided to paint this amazing mural as a gift to Pisa. Though extremely large, it is easy to miss so look out for it; it is located between the train station and Corso Italia.