TOTEM (4D Trento Time Machine) is a project funded by Fondazione Caritro (Cassa di Risparmio di Trento e Rovereto), focused on the valorization of historical and archival data of the city of Trento.

The augmented reality application of TOTEM allows the users to visualize historical photos of Trento in four areas of the city centre. The photographs, capturing events and changes of the city in the last century, are visualizable from their acquisition position.