The site of Hadrian’s villa at Tivoli covers over 120 hectares, developing over tufa plateau’s on different levels. The structure of the so-called Academy is situated on the uppermost platform which extends towards the south. Brick stamps date the buildings to 132-124 A.D. In 1621 the complex became part of the Bulgarini property. The name Academy and its function are conventional and date to the mid 16th century when Pirro Ligorio assigned the nomenclature given in a famous passage by Spartianus (Script. Hist. Aug., Hadrianus 26,5) to the buildings of Hadrian’s Villa. There are no certain attestations of the real function of this complex, however, the finds and the presence of extremely fine mosaics suggest that it was used by the imperial family. The investigations had two distinct objectives. The first objective was to find a tract of one of the many underground routes that are one of the most fascinating characteristics of Hadrian’s Villa. The second objective arose from the hypothesis, formulated on the basis of typological and functional parallels, suggesting that a hydraulic structure stood at the centre of the Academy’s courtyard. By this term a pool or fountain is intended, architectural elements that were nearly always present in Roman gardens. The most impressive result was without doubt ascertaining the precision of Piranesi’s 1781 survey of the underground routes. Using a CAD plan as a reference, a hypothetical reconstruction was made of a stretch of the route. Only the planned continuation of investigations will establish with greater precision the branches of the underground networks in this area. As regards the second objective, the plans produced by the resistivity survey did not confirm the whether or not a hydraulic structure was present. The signals registered did not consent a clear reading. However, a good base was laid which offers an interesting and alternative research method in a context where, at present, there are no prospects for excavation.