About 400 metres from the Medici pier and 52 metres tall, the "Pisans’ Lighthouse" is formed by two superimposed crenellated towers with a truncated cone base. It was destroyed by bombings in 1944 and rebuilt in 1955. The original must probably be attributed to Giovanni di Nicola Pisano, who built it in the same years that he was working on the pulpit of the Cathedral of Pisa. The edifice was built near the city to replace the Meloria Tower, sited on the shoals west of Livorno and irremediably damaged by the Genoese in the famous homonymous battle (1284), which saw them victorious over the Pisans.

Florentine chronicler Goro di Stagio Dati defined the Fanale as one of the most beautiful lighthouses in the world; it is even believed that it was the source of inspiration for Dante Alighieri in his famous verses «stand like a sturdy tower that does not shake / its summit though the winds may blast» (Divine Comedy, Purgatory, V, 14-15). The tower is also reported by Francesco Petrarch in his Syriac Itinerary as «very effective, every night, the flame on top guides sailors to the safest shore». By order of Grand Duke Francesco I de’ Medici, in 1584 it housed a lazaretto. The tower is also an emblematic site tied to Galileo Galilei who performed numerous experiments here to fine-tune his telescope.