Structure N10-9 is a Classic Period pyramidal temple with a small shrine room near the bottom of the stair and a vaulted building of two rooms about two thirds the way up the stair. The pyramid top had been disturbed but appeared to have been an open area with nothing in the way of an altar.

Sketch reconstruction of N10-9 in the Early Classic Period based on measured dimensions and accurate perspective projection. Red paint is evident is a few places and assumed all over. An unusual feature is absence of apron moldings on terraces. Formation is that of an eight-terrace pyramid on a basal platform. The basal platform is similar enough to the terraces that a nine-terrace formation could be understood also. Location of the building below the top of the pyramid is a feature found elsewhere at Lamanai, at Altun Ha, at Caracol, at Uxmal and at other urban centers.

Core masonry of N10-9 includes rubble, chert boulders, and very weak, earthy mortar. The broad proportion reflects this relatively unstable type of construction.

Structure N10-9 in the Late Classic Period. The basal masks have been partially delmolished and covered up. Original terraces are still in use, their paint now faded. New teerraces have been built along the front to sustain a new building higher up but still below the level of the pyramid top and a new set of stairs has been installed.
Structure N10-9 in the Early Post-Classic Period. Original terracing has partially decayed. The Late Classic building is still in use but new terraces have been built out in front and above it together with a new stair. These terminal additions have not been painted. The assumption that tree may have taken root on the rear parts of the substructure is hypothetical.
Structure N10-9 at start of excavation in March, 1976. Trees and underbrush have been removed. Stumps are left for stability beyond excavation limits and for removal by cutting of all roots in excavation areas. Material removed so far is collapse debris. Exposure of insitu surfaces began at uppermost point of survival at re-entrant corners where geometry results in maximum preservation.
At this point, later in the month, collapse debris has been removed exposing intact surfaces at the north-west corner. Traces of red paint are visible on primary terracing of the Early Classic pyramid. Rough-looking masonry projecting out to the left is that of the Post Classic terminal addition. These terraces, lacking red paint abut primary red-painted terraces.
The entire north-facing front has now been cleared and axial trenching has been started. The axial trench cut through several superimposed stairs including one stair that had been almost entirely ripped out. The stratigraphy was relatively complex here and would have been incomprehensible if excavation had been limited to the axial area. Because of weakly mortared core masonry a deep trench was not possible. The axial excavation revealed presence of earlier construction that had been almost completely demolished prior to installation of the main pyramid. It was not possible to determine the nature or magnitude of the earlier work.
The east side mask on the basal terrace. Ear ornaments flank the central feature. there appears to be a large mouth recess with a central snout-like projecting element with what looks like three teeth. Above that are two split openings that may be serpent eyes. Elements above this point have been lost due to collapse. Surviving features were protected by later terracing that had subsequently been removed to re-expose the mask. Only the plaster turns at floor level remained as evidence of the period when the masks were hidden. A few traces of red paint remained in recesses. The mask may combine serpent and jaguar features. East and west masks appear identical in surviving parts.