The river Arno as an axis of economic development in Tuscany: a function which has been extinguished - Water Tuscany Arno Navigable Rivers This essay is concerned with the conveyance of goods by rivers, the Arno and its tributaries, and navigable waters in the Grand Duchy of Tuscany in the years between 1737 and 1859, the period of the Augsburg Lorena rule. The political-administrative organisation, and geographical and technical aspects are taken into account: the Arno as a border and at the same time a connection; the infrastructures of the river navigation, boats, and the politics of Lorena’s rule according to Enlightenment values. The change of values, whit the elimination of the privileges and the bonds, like the special prices of corn and fresh-water fish, lead to the transformation of the lake of Bientina, and same decades after of the lake of Fucecchio, into cultivated fields, in favour of landed property.