The Arno Valley of the Balze

The Arno Valley of the Balze

Since the Renaissance the Upper Arno Valley has been known as an extraordinarily important and rich fossil site both for the quantity and quality of the fossils which bear precious witness to our most ancient history. The geological conditions of the Arno Valley are in fact singular and have allowed the fossilization of heterogeneous flora and fauna which tell the story of life in the territory up to 3 million years ago. One of the naturalistic peculiarities which makes the Arno Valley unique and immediately recognizable are the Balze (crags) formed by the accumulation of deposits caused by the incessant flow of ancient water courses. As a result these imposing layers of sand, clay and conglomerates were formed over thousands of years, and can reach heights of up to 100 metres. They give the landscape flashes of intense warm colours, and are typically yellowish in colour. Gorges and dips between the Balze make the landscape unique and suggestive.
The Balze are precious treasure chests which preserve traces of the past. At their feet in particular, buried under layers of earth, are the fossilized remains of the fauna which populated the Arno Valley during the Final Pliocene – Early Pleistocene era (2.6 million years ago).


The fauna of the time is typical of a climate similar to the current climate of the African savannah, and examples can be found in the Museo Paleontologico dell’Accademia Valdarnese del Poggio in Montevarchi. There we can find rhinoceri, hyenas, hippopotami, felines, canids, giant cervids, and recently discovered elephants.
The Balze geologically unite the Arezzo and Florence Arno Valley at the foot of Pratomagno, creating a sort of bank similar to a Grand Canyon which has its corresponding, if less imposing, structure in the Smotte on the left bank of the River Arno. Highly recommended is the Acqua zolfina route, a circular path which offers visitors the most suggestive landscape and views.

The Balze geologically unite the Arezzo and Florence Arno Valley at the foot of Pratomagno, creating a sort of bank similar to a Grand Canyon which has its corresponding, if less imposing, structure in the Smotte on the left bank of the River Arno.
Highly recommended is the Acqua zolfina route, a circular path which offers visitors the most suggestive landscape and views.