Just 80 miles east of Merida, on a highway that cuts almost straight through dry scrub forest towards Valladolid and Cancun, ChichenItza suddenly looms above the treetops. It's an impressive sight Early information about the six-square-mile site and its hundreds of structures is sketchy.

Chichen-Itza was built late in relation to more southerly Mayan areas. Major buildings weren't begun until possibly 600 A.D. Late in the 10th century the Toltecs arrived from central Mexico, following their god/ruler Quetzalcoatl in 987 A.D. This god, the Plumed Serpent, is known here as Kukulcan.

At about the same time a new group arrived from the southem part of the peninsula. Considered "tricksters and rascals" by the natives, the newly-arrived Itza proceeded to take charge. Eventually they moved on to northem Guatemala, where they established an equally poor reputation.

The architectural and artistic differences between the older pure Mayan constructions and the newer T oltec-inspired sections is pronounced. When the Spaniards arrived in the 16th century, the city had been reclaimed by the jungle.

In 1885 the U.S. consul in Yucatan, Edward H. Thompson, purchased the abandoned site. In 1904 he dredged the Cenote Sagrado, or Sacred Well, and verified the legends of sacrificial humans and valuables being cast into the sinkhole as offerings to the Mayan gods. Offerings to Chaac, the crooked-nosed rain god, were particularly significant in this lakeless, riverless region where water was precious. In the 80-foot well, Thompson found the remains of human bones and 240 artifacts of jade, copper and gold. The Carnegie Institute continued to explore the area from 1923 to 1943.

The dominant structure at Chichen-Itza is El Castillo (also known as the Pyramid of Kukulcan), 75 feet tall and capped with a square temple. You climb 91 steps to the top. The total numher of stairs is 365 (there is one top step), a figure which attests to the Map's knowledge of the heavens.

Twice a year, during the spring and autumal equinoxes, thousands gather around the Kukukan Pyramid for a spectacular show.
Mayan architects designed the pyramid so that the afternoon sun at these times of the year produces the shadow of a snake (representing the Plumed Serpent deity) descending the staircase, its giant head resting at the base.

Kukukan is built over a series of prelvious constructions. An interior staircase leads to the Throne of the Red Jaguar, a chmber containing a reclining Chac-Mool and a stunning, popeyed jaguar. Access to the chamber is from 11: 30 a.m. to 3 p.m. and 4 to 5 p.m.

To the west of Kukukan is the great 272 foot-long Ball Court where the Maya played a ball game popular in many parts of Mesoamerica. Friezes show the ganme had religious significance and was played with deadly seriousness: the captain of one team is shown being decapitated. What is intriguing is that experts cannot say with any certainty whether he represents the winning or losing team. Sacrifice was not only accepted, but considered an honor in serving the gods. Chichen-Itza has 22 ball courts. more than have been found at any other Mesoamerican site.

Aesthetically beautiful and unique in Mesoamerica is the Observatory, a circular dome built atop a massive terraced temple in the old, Mayan section. A circular interior stairway leads to a chamber at the top tht served as an observatory fo astronomers. Small slits in the wall provide fixes on celestial bodies, and the readings were used to calculate agricultural timetables.

Nearby is another complex, the Nunnery and Church. A massive structure 300 feet long and 55 feet high, it is full of connecting rooms the Catholic Spaniards interpreted to be a nunery. The gaping hole in one side was made by an early French explorer who dynamited the building to see what was inside.