North side of Structure IV and its Annex
Typical Becan architectural motifs decorate the annex to Structure IV, seen to the right in the photograph. A different type of decorative wall treatment adorns the terrace at level 2 of Structure IV.
"The north facade is completely different from the others with many doorways opening into numerous rooms. Even without the doorways at Level 3, which are conjectural, the north side of Str. IV must have been much less austere and formidable than the others. By far the most important rooms here are those at Level 2, essentially at the same level as the plaza to the south of the structure."
(Potter, p. 16-25)