The "mallos" are a set of vertical walls that stand out like the ruins of an imaginary city. Erosion has gradually carved out large red ochre sugar loaf formations, the most dramatic of which can be seen to the right of the A132 road, where their flame-red structure seems to completely dominate the village of Riglos, huddled around its 12C Romanesque church. The largest colony of vultures in Aragón nests in the Mallos.