The greens, whites, pinks, browns and greys that make up the Florentine palette are some of the city's most recognizable visual cues. Not solely chosen for their esthetic value, the colors of Florence represent the wide range and rich variety of building materials that were available to the Florentines at various times during the city's history. Due to the fact that Tuscany is naturally an area rich in geological formations, caves and quarries, stones such as pietra serena, pietraforte and pietra bigia have played a large role in the shaping of the Florence city landscape. This two-hour walk will explore this close link between building material and geographical/territorial history, as seen in some of the most cherished landmarks in the city center. Starting from the multicolored curlicues of Alberti's elegant facade of Santa Maria Novella, the walk will wind its way through Florence's compact historical center, ending at the monolithic Palazzo Pitti. The churches, government and civic buildings, markets, bridges and houses that we will ponder during the course of the walk provide a living narration of the architectural and engineering history of the city. The importance of preservation and restoration of the architectural landmarks of the city will also be evident, as one clearly witnesses the devastating effects of modern-day pollution on these structures and the efforts being made to counteract them. This walk will be led by an architectural or city-planning scholar who will be able to analyze, at length, the important link between city and material. The time spent together will strive to train our eyes, too often crowded nowadays by modern technological imagery, to perceive the stunning architectural aspects endowed to Florence through several centuries, as not only a form of urban development but also as an esthetical program and a form of profound civic pride.