The descriptions here I have pulled from http://www.chichenitza.com/ I (of course) cannot guarantee their historical accuracy (can I hear a DUH!)However I can tell you it is a remarkable site, and there is MUCH more to be seen than what I have included here.
The major feature of the the site is the "Great Ball Court" (El Gran Juego de Pelota). "The Mayans were great sportsmen and build huge ballcourts to play all their games. The Great Ballcourt of Chichen Itza is 225 feet wide and 545 feet long overall. It has no vault, no discontinuity between the walls and is totally open to the blue sky.
Each end has a raised to the temple area. A whisper from end can be heard clearly enough at the other end 500 feet far away and through the length and breath of the court.
The sound waves are unaffected by wind direction or time of day and also night. Archaeologists engaged in the reconstruction noted that the sound transmission became more and more strong and clear as they proceeded.
In 1931 Leopold Stokowski spent 4 days at this site to determine the acoustic principals that could be applied to theater for an open-air concert he was designing. Stokowski failed to learn the secret. To date it has not been explained.
It is easy to imagine a Mayan King sitting here presiding over the games. Legends say that the winning Capitan would present his own head to the losing Capitan, who then decapitates him."
Note the hoop in the wall.
The Castle (El Castillo - the Kukulkan Pyramid):" The Kukulkan Pyramid was built for astronomical purposes and during the vernal equinox (March 20) and the autumnal equinox (September 21) at about 3pm the sunlight bathes the western balustrade of the pyramid's main stairway.
This causes 7 isosceles triangles to form imitating the body of a serpent roughly 37 yards long that creeps downwards until it joins the huge serpent's head carved in stone at the bottom of the stairway."
The Sacred Cenote (Cenote Sagredo): "The Yucatan Peninsula is a limestone plain, with no streams or rivers. The region is pockmarked with natural sinkholes ( Cenotes ) which expose the water table to the surface.
One of the most impressive is the Sacred Cenote, which is 60 m. in diameter, and shear cliffs that drop to the water table some 27 m. below.
The legendary Sacred Cenote (natural waterhole) of Chichen ltza was special to the people for its social and religious significance. On occasions, the sacrifice of human life was part of the offerings made to the Water God. But, it was not as common as had earlier been imagined."
