'The bridge takes its name from its first builder, Lucio Fabriclus, who built it in 62BC to join the left bank of the Tiber with Tiber Island. It is built of tuff and peperino, faced with travertine, and is 57.30m long and 5.60m wide.
It is also know as "Bridge of the four heads" because of the two herms of Janus that were placed on the two parapets in 1848.
The legend tells that the four faces represent the architects who restored the bridge; later Pope Sixtus V, Felice Perretti (1585-1590) had them beheaded because their lifestyle was far from exemplary.
Urban II, Ottone dei Signori di Chatillion (1088-1099), one of the greatest popes in the history of the Church, was imprisoned in the Ceaetani tower, which faces the bridge.
It is known that there were mills in ancient Rome as far back as 109AD, when Emperor Trajan had an aqueduct built to bring water from Bracciano to the Janiculum Hill, on the slopes of which there were several mills exploiting the fall of the water that flowed plentifully down from the mountains. the mills were moved to the river in 573 AD when, in order to conquer the city, Vitige the barbarian cut off all the 14 aqueducts supplying Rome with water.
Tiber Island was an ideal place for them: with its two lateral branches in which the flow of the water was stronger it had the right hydraulic characteristics for the floating structures.
A census in 1746 counted eight mills all near the island, anchored to the pylons of the bridges or close by. The work of the floating mills came to a complete end with the last disastrous flood of 1870. The tendency of the left branch to silt up, favoured by the presence of semi-submerged ruins and the many mills that hindered the regular flow of the water, led to a proposal, in the plan for the hydraulic settlement of the river in 1980 to eliminate this branch completely.
If this had been put into effect the beautiful view of the island would now be merely a memory of the past.'