that is a difficult question, it depends upon what point you take as the lip and where you measure the lowest point. If we assume the lowest point to be at latitude 42.65 and longitude -0.1016 which is near Puente de los Navarros (Bujaruelo) this is at an altitude of 980m. Now you could possibly say that Monte Perdido is the aforementioned lip at 3355m, giving us a depth of 2375m.
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