A vendor hopes to make a sombrero sale at one of the pyramidal structures near the Pyramid of the Moon.

One of the fourteen pyramidal structures surrounding the Pyramid of the Moon. 

Central altar located in the Plaza of the Moon as viewed from the Pyramid of the Moon.  The north end of the Avenue of the Dead can be seen running to the south with the Pyramid of the Sun to the east.

Close up of stone work

Map of Teotihuacán complex

Architectural elements within the altar are precisely aligned to the Sun and its 9 known planets in addition to a 10th planet (perhaps Sedna?).  Therefore, the interior is divided into 11 altars, 10 of which are built with one side touching the outer wall while the 11th lies exactly in the center.  The design is explained at length in the Fejervary-Mayer codex where it discusses the cardinal points and the intermediate ones that place the abode of the gods with birds, trees, and the distinct colors that divide time and space in the day count as stated in the legend of the creation of the Universe.

Stretching 2 miles from the northern end of the Plaza of the Moon to the southern horizon of the Ciudadela (and beyond), the Avenue of the Dead seems to run in a smooth continuous flow; however, closer examination indicates that a stepped slope was achieved by deliberately cutting into the native rock.  Overall, the drop from the Pyramid of the Moon to a point past the Ciudadela is some ninety feet. Six segments have been created by the erection of a series of double walls perpendicular to the course of the Avenue. The Avenue's cavity is further lined with walls and low structures, resulting in six semi-subterranean compartments open to the sky. The perpendicular walls are fitted with sluices at their floor level. The theory is that the whole complex served to channel water down the Avenue beginning at the Pyramid of the Moon (where a subterranean tunnel was found to encircle it) and possibly linked it to the subterranean tunnel of the Pyramid of the Sun. The series of compartments then retained and eventually let out water from one to the other until ultimately the water reached the diverting channel of the San Juan River.  It should be noted that a statue of the goddess of water, Chalchiuhtlicue, was found at the foot of the Pyramid of the Moon.