The Umbrian Valtiberina includes that part of the territory of the province of Perugia located within the municipalities of: Citerna, Città di Castello , Lisciano Niccone, Monte Santa Maria Tiberina, Montone, Pietralunga, San Giustino and Umbertide .
The agricultural vocation in the sharecropping area finds spatial translation in the typology of the scattered settlement. The settlement concentrations in Città di Castello, San Giustino and Umbertide were determined by mechanized agriculture and the development of manufacturing activities . The modernization processes of agriculture were supported by artisanal productions ( paper, typography, period furniture, fabrics ) which gave vitality to the industrialization of the valley with machinery factories and agri-food establishments .
The Valtiberina identifies a stretch of the upper course of the Tiber river, which develops with a north-south orientation from Albiano (in the Arezzo area) to Umbèrtide . To the north, between Sansepolcro and San Giustino, the only administrative border passes between Tuscany and Umbria, inherited from the fifteenth-century political organization and significant of a historical vocation to bipolarity. The fragility of territorial integration is in fact a phenomenon already defined in the Middle Ages, when the two portions of the valley are divided into "Piano di Sopra" and "Piano di Sotto", the first gravitating on Sansepolcro and the city of Castello, the other on Perugia.
As for the geographic scope it is defined by the surrounding mountainous regions. To the north-west the valley is separated from the Arno basin by a series of elevated peaks between 974 m of Alpe di Poti and 1415 m of Monte il Castello , the summit of Alpe di Catenaia. To the east, the watershed with the Marecchia is marked by the ridge of Alpe della Luna at 1454 m, with the passes of Bocca Trabaria at 1049 m and at Bocca Serriola at 730 m. To the south, Mount Acuto marks its limit at 926 m.
Human settlement in the upper Tiber valley has been favored by a habitat rich in water and a clayey-sandy substratum. The intensification of the population had to take place above all in the Neolithic. In the pre-Roman age the Tiber became the reference border between the Etruscans and the Umbrians, the former settled on the hydrographic right (west) and the latter in the territory on the opposite bank; the cities that rose along the banks naturally enjoyed a privileged position, especially as the river, navigable for a long stretch, allowed the transport of goods in both directions, thus relating the centers of the Tyrrhenian coast to those of the interior. In Roman times, the Tiber, no longer a borderline between different nations, was used as a great communication and supply route for the capital.
At the time of the Lombard domination, the Val Tiberina remained under Byzantine control as part of that "corridor" that connected the Exarchate with Rome. In the communal age, alliances, clashes and consequent dependencies marked the events of the area, where the political interests of Arezzo, Perugia and Montefeltro came into conflict with the will of autonomy of the Municipalities, first of all Città di Castello to whose diocesan territory it belonged. , between the thirteenth and fourteenth centuries, for almost all.
The affirmation and persistence of the role of a real city exercised by Città di Castello, endowed with ample political and cultural autonomy up to the entire fifteenth century, is a peculiar phenomenon of the upper Tiber valley , a borderland and eccentric compared to the areas of influence of the great centers of power. This hegemony, which under the lordship of the Vitelli finds full expression also in the strictly artistic and cultural sphere, is projected into the agricultural countryside full of villages and villas, in which the city is the only organizing center.
In the southern portion of the valley, on the other hand, the great Benedictine abbeys structured the territory between the 11th and 13th centuries, starting those processes of agricultural colonization of the plain and the exploitation of the mountain that will be completed with the reclamation and deforestation promoted by the Perugian Municipality, in the to which you dominate the Piano di Sotto up to Umbertide it became part of it between the 13th and 14th centuries. The articulation of the spheres of political power and the need to control the important communication route generate the phenomenon of fortification, which disseminates an exceptionally dense and widespread network of fortifications. The definitive administrative division of the valley traced by the current regional border is due to the political agreement between the Church and the Florentine state, ratified in 1441 by Pope Eugene IV and Cosimo the Elder.
The favorable environmental conditions have always allowed an intense agricultural exploitation, both in the valley floor, rich in water, and in the hilly area, especially on the hydrographic left, which is wide and sunny, while on the other side the wood cover prevails. The vine is widespread in particular in the municipalities of Città di Castello and Umbertide, where it alternates with the olive tree, which is generally less extensive; in the hilly area the polycultural forms prevail which, together with the exploitation of the woods and chestnut groves on the mountains, now depopulated, constituted in the past a significant voice of the traditional economy.
The exploitation of the fertile soils of the irrigated plain, where the cultivation of tobacco is practiced, has always been of fundamental importance. Introduced in Sansepolcro in 1575, it was a source of wealth for the Frankish territory of Cospaia , on the border between the papal and Medici states to which it had no fiscal obligation. When Cospaia passed under the control of the Church in 1826, the profitable cultivation extended throughout the area (today it is concentrated above all in the Tifernate), becoming the basis of the Valtiberine agricultural system and a characterizing element of the agricultural landscape. Monumental testimonies of artisanal tobacco growing are the large indirect fire dryers, now mostly in a state of neglect but easily recognizable for the numerous chimneys that have become a typical presence in the countryside.