The Tuta Gran is the historic and most usual access to the system. Past the entrance (with the remains of an old grille), about 2.5 metres wide and with forms that reveal its action as a spring in past times, we find ourselves in a vestibule of regular dimensions with a floor that has been greatly modified by archaeological excavations. To continue we are presented with two main options: if we follow to the left we will go to the galleries of the Tuta Freda. If we continue straight we will access the best-known and most important sector of the system. There is still a third section, in a SW direction, ascending through a widened joint in the form of a chimney, reaching a small gallery that leads directly to the outside (TUTA DE DALT).

From the entrance hall and after about 25 metres the gallery bifurcates. Continuing straight we will access the lower galleries, while if we turn right, going up a short ramp, we will find ourselves at the start of the upper galleries. Both sectors meet again at the Sala Cerdanya after more or less complex routes.

The Galeries superiors: The first metres are narrow and it is necessary to crawl in some places. After a small downward step the gallery we are following has an intersection with another of larger dimensions which we will follow to the left, where the gallery widens, acquiring a section clearly determined by the bedding, presenting large blocks of parallelepiped shape, the major faces coinciding with bedding planes. The gallery opens at the upper part of the Sala Cerdanya, which is reached by descending a slippery ramp.

About 60 metres above the Tuta Gran is the TUTA DEL BOSC, a small cave known for a long time and which, after hard desobstruction work, could be advanced through a series of very narrow passages and some step that allows reaching the entrance of a 10-metre pit. At the same height as the entrance of the pit there is a window which, by means of a handrail, allows access to a beautiful ascending gallery that remains closed further on. In its central section is the level + 10 (with respect to the Tuta del Bosc, which is now level 0 of the system) the highest point of the whole system. At the base of the 10-metre pit a beautiful gallery with a perfect vault starts, with a narrow descending bifurcation on the left. Following the main gallery one reaches an inclined pit and further on a new narrow passage that had to be desobstructed. Once passed, one enters a descending tube and then a small room, a narrow passage and a mud slide, downclimb a 4-metre chimney and access a pronounced ramp that is already part of the Galeries superiors of the Tuta Gran.

Also, 5 metres above the Tuta del Bosc and shortly after entering it, there is a narrow impenetrable chimney that connects with the outside, the Tuta del Conill (level + 5).

The Galeries inferiors: It is a set of galleries of apparently irregular layout, with continuous widenings and narrowings, although the average sections are usually modest. After a relatively important route we will reach the lower part of the Sala Cerdanya by means of a passage clearly structured in a fault. This is a sector with a much more youthful morphology than the upper galleries; corrosive forms become evident as we approach the room.

The Galeria Canela: Its access is from the lowest point of the Sala Cerdanya, where we find a muddy small sump that must be emptied each time (it is quite a task to do so and in rainy periods it does not take long to fill up again). Once emptied, a short but unpleasant crawl places us on the other side (it should be said that in recent times the dimensions of the passage have increased and a flat board has been placed to allow the explorer's body to slide). Once the passage is passed, a room of considerable dimensions suddenly opens. The Galeria Canela consists of a main conduit from which some secondary branches emerge. It presents a first section of ascending layout and, after a 10-metre climb (which can be avoided by passing through some crawls), it becomes descending while its morphology changes, since the formations reach great spectacularity. The gallery ends filled with sediments, after having completed the most beautiful route of the whole cavity.

Just above the access to the Galeria Canela, at the highest part of the room, the so-called Galeria Martinet develops, which in total has a length of 92 metres.

The Tuta Freda: A wide entrance (6 x 2 m.) gives access to two galleries that join after a few metres. On the left the passage ends in a small room one metre high with the floor covered by abundant blocks. To the right is the crawl that was desobstructed in 1962 and once passed one enters a zone of blocks up to a small room of larger dimensions. An ascending conduit leads to the junction zone with the gallery that descends from the left of the entrance hall of the Tuta Gran. In this sector there are many bifurcations and crawls that lead to a set of quite labyrinthine galleries. Once one reaches the Galeria Badalona this presents a conduit that tends to become wider as one advances until reaching a room with a high vault where at its bottom is the sump. Its level is very variable depending on the rains. When these are very abundant it overflows and many times all the galleries of the Tuta Freda are flooded and the flow comes out through the cave entrance.

The whole flooded conduit begins with a descending gallery to later gain horizontality and then ascend. Further on it descends again and one reaches the point of maximum depth of the system (level – 196) from the entrance of the Tuta del Bosc (level 0). The route of the sump is estimated at 1050 metres.

Current speleometry of the whole system: Vertical range: 206 m. (- 196; + 10) Length: 4246 m.

The spring of la Fou flows at the foot of the Serrat de la Quera, its waters being channelled for use. The muddy small sump of the Galeria Canela must be emptied each time and in rainy periods it does not take long to fill up again. The level of the sump of the Galeria Badalona is very variable depending on the rains; when these are very abundant it overflows and many times all the galleries of the Tuta Freda are flooded and the flow comes out through the cave entrance. The route of the sump is estimated at 1050 metres.

The Tuta Gran is the historic and most usual access to the system. Past the entrance (with the remains of an old grille), about 2.5 metres wide and with forms that reveal its action as a spring in past times, we find ourselves in a vestibule of regular dimensions with a floor that has been greatly modified by archaeological excavations. To continue we are presented with two main options: if we follow to the left we will go to the galleries of the Tuta Freda. If we continue straight we will access the best-known and most important sector of the system. There is still a third section, in a SW direction, ascending through a widened joint in the form of a chimney, reaching a small gallery that leads directly to the outside (TUTA DE DALT).

From the entrance hall and after about 25 metres the gallery bifurcates. Continuing straight we will access the lower galleries, while if we turn right, going up a short ramp, we will find ourselves at the start of the upper galleries. Both sectors meet again at the Sala Cerdanya after more or less complex routes.

The Galeries superiors: The first metres are narrow and it is necessary to crawl in some places. After a small downward step the gallery we are following has an intersection with another of larger dimensions which we will follow to the left, where the gallery widens, acquiring a section clearly determined by the bedding, presenting large blocks of parallelepiped shape, the major faces coinciding with bedding planes. The gallery opens at the upper part of the Sala Cerdanya, which is reached by descending a slippery ramp.

About 60 metres above the Tuta Gran is the TUTA DEL BOSC, a small cave known for a long time and which, after hard desobstruction work, could be advanced through a series of very narrow passages and some step that allows reaching the entrance of a 10-metre pit. At the same height as the entrance of the pit there is a window which, by means of a handrail, allows access to a beautiful ascending gallery that remains closed further on. In its central section is the level + 10 (with respect to the Tuta del Bosc, which is now level 0 of the system) the highest point of the whole system. At the base of the 10-metre pit a beautiful gallery with a perfect vault starts, with a narrow descending bifurcation on the left. Following the main gallery one reaches an inclined pit and further on a new narrow passage that had to be desobstructed. Once passed, one enters a descending tube and then a small room, a narrow passage and a mud slide, downclimb a 4-metre chimney and access a pronounced ramp that is already part of the Galeries superiors of the Tuta Gran.

Also, 5 metres above the Tuta del Bosc and shortly after entering it, there is a narrow impenetrable chimney that connects with the outside, the Tuta del Conill (level + 5).

The Galeries inferiors: It is a set of galleries of apparently irregular layout, with continuous widenings and narrowings, although the average sections are usually modest. After a relatively important route we will reach the lower part of the Sala Cerdanya by means of a passage clearly structured in a fault. This is a sector with a much more youthful morphology than the upper galleries; corrosive forms become evident as we approach the room.

The Galeria Canela: Its access is from the lowest point of the Sala Cerdanya, where we find a muddy small sump that must be emptied each time (it is quite a task to do so and in rainy periods it does not take long to fill up again). Once emptied, a short but unpleasant crawl places us on the other side (it should be said that in recent times the dimensions of the passage have increased and a flat board has been placed to allow the explorer's body to slide). Once the passage is passed, a room of considerable dimensions suddenly opens. The Galeria Canela consists of a main conduit from which some secondary branches emerge. It presents a first section of ascending layout and, after a 10-metre climb (which can be avoided by passing through some crawls), it becomes descending while its morphology changes, since the formations reach great spectacularity. The gallery ends filled with sediments, after having completed the most beautiful route of the whole cavity.

Just above the access to the Galeria Canela, at the highest part of the room, the so-called Galeria Martinet develops, which in total has a length of 92 metres.

The Tuta Freda: A wide entrance (6 x 2 m.) gives access to two galleries that join after a few metres. On the left the passage ends in a small room one metre high with the floor covered by abundant blocks. To the right is the crawl that was desobstructed in 1962 and once passed one enters a zone of blocks up to a small room of larger dimensions. An ascending conduit leads to the junction zone with the gallery that descends from the left of the entrance hall of the Tuta Gran. In this sector there are many bifurcations and crawls that lead to a set of quite labyrinthine galleries. Once one reaches the Galeria Badalona this presents a conduit that tends to become wider as one advances until reaching a room with a high vault where at its bottom is the sump. Its level is very variable depending on the rains. When these are very abundant it overflows and many times all the galleries of the Tuta Freda are flooded and the flow comes out through the cave entrance.

The whole flooded conduit begins with a descending gallery to later gain horizontality and then ascend. Further on it descends again and one reaches the point of maximum depth of the system (level – 196) from the entrance of the Tuta del Bosc (level 0). The route of the sump is estimated at 1050 metres.

Current speleometry of the whole system: Vertical range: 206 m. (- 196; + 10) Length: 4246 m.