Photo 33.  GPR profiles of the trench detected about 10 meters east of the Castillo Pyramid.  From upper left-to-right are radar profiles at OO north, 4 meters south, 12 meters south.  Lower left-to-right are profiles
at 14 meters south, 16 meters south and 17 meters south.  Radar transects were made from west to east.
 The dark area represents the trench which is filled by rubble, and the green is plaza constructed
by the Maya.  Note that the trench appears to open to the west (left)  in profiles 14S, 16S,
and 17S toward the east stairway.  Courtesy of William Sauck, 1997.