On 17 September 1871 the Fréjus railway tunnel was inaugurated, the first tunnel in the Alpine chain. 14 years of work, digging 12 km into the mountain, represented an extraordinary technological and scientific challenge. The first part of the volume reconstructs the events and the political context of this collective enterprise in which geologists, engineers, politicians, workers and workers - and the Academy of Science itself both as an institution and through its members - were involved. The Fréjus Tunnel has produced a real revolution in tunnel excavation: from the manual drilling of the mining tradition we have moved on to an innovative mechanical drilling with compressed air, thanks to the ingenuity of Sommellier, Grattoni and Grandis who were the decisive architects of the enterprise. The second part focuses on the construction of modern base tunnels in the Alpine arc, on the technical-scientific progress of recent years and on the development of the European TEN-T transport network which, as happened for Fréjus 150 years ago, today requires new technical, scientific and political challenges for an increasingly interconnected Europe and increasingly sustainable mobility.