It is a peculiar phenomenon. It is a huge ravine dug up in the south ridge which closes the Seaca Valley, with a depth of 100 m and a diameter of 600 m. Throughout its surface, a very active process of erosion removed the layers of quartzite, the red violet color of which gives the area a totally special character, seen from great distances as an open wound in the body of the mountain.
Sharp edges like real blades converge towards its center to thread a dale, dividing the space into several sections. Vâlcelul is a canyon extremely difficult to go downstream because of the high waterfalls.
Interestingly, erosion works very actively even today, digging regressively and rapidly increasing the size of the Ruginoasa Pit. Following the old maps, it is found that erosion has advanced with a very high speed, 80 years ago the place having been marked as only a very small ravine.