The U shaped Uffizi Gallery (Picture 1) (tel.055 238 86 51; Piazzale degli Uffizi 6; open 8.15am, to 6.35pm, Tue-Sun, to 9pm Tue Jul-Sep) houses 1555 works of art in about 50 rooms. A tour can take about 4 hours to complete it if you want to see it all. There is a condensed but complete audio guide lasting 85 minutes to show you around the gallery.
Reservations are highly recommended as queuing can be very extensive especially during peak season.
The commission of the building was given to Vasari by Cosimo I to house the offices of the different guilds, members of the judiciary system and administrators. Vasari also planned the Corridoio Vasariano connecting the Uffizzi, Palazzo Vecchio and Palazzo Pitti (soon available for visitors after restoration is finished).
When Vasari died, the building was under the direction of Alfonso Parigi and Bernardo Buontalenti. The construction, which underwent modifications to house the collection of the family, was finished in 1580. the collection was left to Florence by Anna Maria de ’Medici in her will on the condition that it could never be moved  to any other town.
This museum can be included among the best in Italy and in fact worldwide.
The Museo Nazionale del Bargello and Museo Archeologico have some pieces from its collection and the Uffizi has received collections from other museums. The 1993 mafia car bomb, with a casualty rate of 5 people, damaged some pieces as well as catalogues.
At present there is a project to be finished by 2013 to double the display rooms. The project, a very large investment, is under Arato Isozaki’s direction.
The collection follows an arrangement according to school and in chronological order beginning with Ancient Greece, continuing with Renaissance and finishing in 18th century Venetian painting. Its catalogue can be seen online at  www.virtualuffizi.com
The collection is exhibited on the 3rd floor in rooms along corridors 1 and 3. Corridor number 2 leads to a loggia, a vantage point from where to see the Ponte Vecchio and the Corridoio Vasariano.
Different rooms are closed depending on the day. The information as to which are available can be found at the ticket booth and main entrance to the gallery, or online www.polomuseale.firenze.it/english.
Pieces of art by 13th and 14th century Tuscan artists are exhibited in the first room on the left. Its three altarpieces which were in churches in Florence are displayed here. They were made by Duccio di Buoninsegna, Cimabue and Giotto. Giotto’s masterpiece created over two decades later than the other two artists’ pieces show the change from Gothic to Renaissance style.
As the previous one, the following room houses pieces from the 14th century Sienese school. Among its best pieces is the Annunciation by Simone Martini and Lippo Memmi made in 1333 whose Mary is surrounded by a golden sea. Here is also Pietro Lorenzetti’s Madonna with Child and Saints triptych showing touches of realism like Giotto’s.
The following room devoted to 14th century Florentine artists is a magical cave of realist paintings with strokes of gold leaves and tiny details. Among them is San Reminio Pietà by Giottino, painted between 1360 and 1365.
An enormous room divided into Rooms 5 and 6 holds International Gothic pieces. The highlight is the Adoration of the Magi by Gentile da Fabriano, painted in 1423.
Room 7 is devoted to those who in the first part of the 15th century devoted themselves to improving and including perspective in their artwork, bringing this new innovation to the Renaissance. It can be seen in the Battle of San Romano by Uccello. Of the three panels, only one is here, another is in Paris and the last one in London. The picture depicts Florence defeating Siena and perspective is successfully achieved, apparent in the  way the lances, horses and soldiers are depicted.
Pure humanism appears in the portraits of the Duke and Duchess of Urbino by Piero della Francesca exhibited in Room 8.
Fra Filippo Lippi’s Virgin and Madonna and Child with two Angels painted in 1439-47 and 1460-65 respectively hang here. He portrayed himself in the first picture.
Room 9 is devoted to Antonio and Piero del Pollaiolo. They depicted the seven cardinal and theological values held and cherished by 15th century Florence for the merchant’s tribunal in Piazza della Signoria. With the exception of the value Strength by Botticelli, all of them are Pollaiollos’. Here also hangs the portrait of Galeazzo Maria Sforza by Piero and Portrait of a Lady in Profile by Antonio.
10 to 14 holds Botticelli’s masterpieces, always admired by crowds visiting the museum. Among the favourites are the Adoration of the Magi, Primavera (Picture 2), Madonna of the Magnificat, Birth of Venus and Cestello Annunciation, here named in the order they were completed between 1475 and 1489. Between 1495 and 1500 he devoted himself to painting two miniatures: one is Judith coming back from Holofernes’ camp and the other depicting Holofernes beheaded.
Number 15 belongs to Leonardo da Vinci’s first pieces: his Annunciation painted in 1472 and an unfinished Adoration of the Magi in 1481-2.
At present, Room 18, called La Tribuna, where Francesco I started to store his collection, exhibits the Medici portraits hanging on elegant red upholstered walls. Bronzino’s depiction of Cosimo I’s family is considered among the most attractive.
Renaissance artists from northern Europe are represented in rooms 20 to 23. Among the pieces are the Adoration of the Magi by Dürer, Adam and Eve by Cranach the Elder and Madonna and Child Enthroned with Two Angels by Hans Memling.
Corridor 3 begins with Room 25 where the picture of the Holy Family hangs. It was commissioned to Michelangelo by Agnolo Doni and acquired by the Medici family about 100 years after it was created. Its colours are as bright as they were many years ago.
Room 26 is devoted to Raphael and Andrea del Sarto. Madonna of the Goldfinch and Pope Leo X with Giulio de’Medici and Luigi de’ Medici are  highlights.
Venetian artists are represented in Room 28 among which are 11 pieces by Titian, the Venus of Urbino, Flora and Eleonora Gonzaga, Duchess of Urbino.
It is impossible for Madonna of the Long Neck by Parmigianino not to draw all the attention in Room 29. The following rooms are for Paolo Veronese, Tintoretto, Rubens and Rembrandt.
The Niobe Room, which is number 42, is devoted to the 4th century BC statues of Niobe and her Children, which were in turn reproductions of Greek originals.
Caravaggio and his school are represented on the first floor with pieces such as Bacchus, Medusa dating both to the end of 16th century and Judith slaying Holofernes by Artemisia Gentileschi (1620-21). Caravaggio as well as Gentileschi used the contrast of light and dark giving their pieces an innovative and exciting touch.