[1] In the 13th century, the construction of the Cassero del Sale made the square pivotal for storing salt essential to the city's economy.

[2] In the 19th century, extensive renovations included demolishing towers, transforming the walls into gardens, and establishing the square as "Piazza d'Armi" for military assemblies.

By the late 19th century, the square became a vibrant hub, hosting the weekly market and livestock fairs, gaining the name Piazza del Mercato, which it still holds officially.

[2][3] The square is bordered to the south and west by Porta Vecchia and the curtain wall extending to the Cavallerizza Bastion, where a pedestrian walkway provides access outside the historic center.

[4] At the entrance to Via Ricasoli stands the Palazzo Carmignani, featuring original Art Nouveau decorations from a historic shoemaker's shop.