It is since a century that the two caves are known to the scientific community; indeed, it dates back to 1896 the first visit to the Vigant Cave: on the fifth and on the 9th of September of that year, Olinto Marinelli, accompanied by Marco Geiger and Girolamo Cussigh visited it. He described the initial length of the cavity and the first two little sloping pits that led him to a depth of about 20 metres and where the exploration stopped in front of a rather deep little lake that could not be overcome because of the lack of a “portable boat”. He postulated the hypothesis that the waters that lose themselves in the cave could appear again in the below Cornappo Valley. Subsequently, was mainly Alfredo Lazzarini who found interesting the cavity and, in 1903 concluded a series of adventurous explorations both in the Vigant Abyss and in the pre Oreak Cave, which were joined by Lino Antonini, Giuseppe Feruglio and Renzo Cosattini. After some years and after some sporadic visits, the two caves were once again at the centre of the interest of Udinese speleologists, in particular Giovanni Battista De Gasperi: whilst for the Pre Oreak there was an almost complete study, the Vigant Abyss was explored and topographed along a development of about more than 170 metres and along a drop of about 60 metres that reached the edge of a pit which was esteemed to be over 50 metres deep. In his studies this hypothesis was added to those that were already known about the connection, a series of observations both geological and hydrologic. Other explorations followed however, it is after World War II that researches, especially those about the Vigant, become more frequent and in 1949 reached and overcame the 80 m pit. The reached siphon lake was believed to be the connection point of the two caves, however, during a new exploration led by the Triestino Speleologist Group together with CSIF in 1952 such limit was overcome reaching, however slightly afterwards, a new siphon lake. In 1958, an expedition organized by the Eugenio Boegan Commission Caves of Trieste and the Udinese sodality, finding the “terminal” siphon opened, could walk a down-hilled gallery of about 250 metres that this time led to the real terminal siphon. Further expedition took place between 1965 and 1966. The first attempts of overcoming the pre-Oreak final siphon took place in 1956, however the attempt was successfully reached by Adalberto Kozel of CGEB in 1965.