At the zone of Els Casots, at the surroundings of the medival farmhouse of Can Llopart de la Costa. We find it on top of a little hill that is at the north of the mentioned farmhouse, 331 meters height. From the road of Els Casots comes a road tha leads to the farmhouse of Can Panxa and, through the fields, we get to the tower. It is a medieval vigilance tower which depended on the Subirats Castle for being it the communication or vigilance point between the Penedès depression ant the deep valley of the Baix Anoia. This structure is part of a defense line which connects the medieval buildings including the Castles of Gelida, Olèrdola, Subirats and other strategy constructions. It seems to be a work of the firt third of the 12th century. Despite of that, there are some signs which points to the idea that it could date further back due to the fact that it was subsidiary to the Subirats Castle, of which there exists documentation dating back to the year 917. It seems to be a work of the firt third of the 12th century. Despite of that, there are some signs which points to the idea that it could date further back due to the fact that it was subsidiary to the Subirats Castle, of which there exists documentation dating back to the year 917. It has a circular plant, a conical body about 10 meter heigh. Interiorly, it has a diameter of 2.1 meters and the thickness of the walls is 1.25 meters, being the heighest part notably thiner than the lowest. The interior is divided in two great parts: a lower one, 3.3 meter heigh, covered with a false dome, to which one can nowadays access through an opening at the level of the ground, made in recent times, and a higher one, 4.3 meter heigh, also covered by a false dome in which there is a cover that gives access to the roof. The crowning walls, with great battlements, with a height of 80 cm. Its original structure is practically intact, it has a first floor with a semi-spherical curve, with the trap to access it. This floor has a window with a defined interior; follows it a modern “trespol” completely drowned and crowned by the ceiling of the tower in a semi-spherical way, with seen work, well-kept. Both the main door and the window are facing west. Some spy-windows can be seen. Its interior was modified at the moment of being used as a dovecot possibly from the beginnings of the low medieval, when its initial purpose, the militar one, disappeared, at least in a continuous way. The primitive entrance to the tower can be found at 3.5 meters from the exterior ground, it was facing west and it gave access directly to the heighest ground. The opening of this entrance is still kept, but the lintel (formed by two “carreus” disposed in angle) and the stone “brancals” have been stolen. At several points of the walls, some spy-windows can be seen, formed by four stones at each side. It was inhabited until the present time. Even though it has a good conservations state in all its essential aspects, it is, unfortunately, in risk of partially crumbling, or even completely. In the spring of 1999 an important part of the exterior wall of the tower fell at the bottom. The recent diagnosis of the structural problem tells that it is directly related to the state of the ground that holded it up rather than its walls. Under the geological rock layer that holds it up there is a weaker clayey layer which has progressively been eroded at the talus near the tower. This eroding is the cause of fissuring of the foundation and the walls, which puts in risk the conservation of the tower. It is one of the most interesting models of the Penedès which has a good conservation, so it requires an immediate acting on it. Nowadays, the owners, Caves Fereixenet, have already shown interest on its conservation, and they have prepared a project of structural consolidation of the construction and the start of the work seems near.