 They are virtually identical and were placed on a north-south line.It is believed that this is a regional variant of a E-Group Complex which is an astronomical observatory named after Group E at Uaxactun.From a point near the middle of the plaza, an observer would see the sun rise over the top of Structure 2 on the morning of the Summer Solstice and over the top of Structure 3 on the morning of the Winter Solstice.