"The two towers, whose essential formal features fit perfectly within the regional style, nevertheless present a series of uncommon traits. On the one hand, a narrow vaulted passageway passes under the stairways (a feature very common at Edzná and in the northwest of the peninsula in general, but in this region up to now we have seen it only in the case of this and other buildings at Hormiguero). On the other hand, its steps, less steep than usual, lead to a platform containing the remains of four thick piers that once supported a vaulted roof, crowned, perhaps, by a comb. All of this contributes toward giving these simulated temples a greater exterior appearance of reality, and seems to indicate that in this particular case they might have occasionally been used for more concrete ritual purposes. Each of the wings of the building still has, on the sides of the now-ruined doorways, one of its door jambs that, cut out from the thick wall, looks like a large embedded column topped by a quadrangular capital."
Paul Gendrop, Rio Bec, Chenes and Puuc Styles in Maya Architecture, p. 57-59.