Ancient latrines
The Palace was outfitted with ancient latrines:
Fitted with plumbing that draws on the ancient aqueduct, the Palace was a comfortable building. It seems to have served as the focus for the various royal ceremonies, rather than as a residence for the king’s family. It was not filled with the sounds of children or the smells of cooking. Instead, domestic structures no doubt adjoined the Palace, perhaps across the aqueduct.
Mary Ellen Miller, The Art of Mesoamerica from Olmec to Aztec, p. 128
Ancient sweat bath
Sweat baths were used by the ancient Maya for both physical and ritual cleansing. This area was presumably used by the participants in preparation for rituals taking place within the Palace complex.
Beyond the wall seen in the top left of the photo is the courtyard between House D and House C. The Tower is located behind the rear wall of the steam room in the upper right.