Kʼatun in the context of Mesoamerican Long Count calendar

A twin-pyramid complex or twin-pyramid group was an architectural innovation of the Maya civilization of ancient Mesoamerica. Twin-pyramid complexes were regularly built at the great city of Tikal in the central Petén Basin of Guatemala to celebrate the end of the 20-year kʼatun cycle of the Maya Long Count Calendar. A twin-pyramid complex has been identified at Yaxha, a large city that was 30 kilometres (19 mi) to the southeast of Tikal. Another has been mapped at Ixlu, and Zacpeten appears also to possess at least one twin-pyramid complex and possibly two. These examples outside of Tikal itself indicate that their cities were closely linked to Tikal politically.

The basic layout of a twin-pyramid complex consists of identical pyramids on the east and west sides of a small plaza, with a walled enclosure to the north housing a sculpted stela-altar pair and a range building to the south. Plain monuments were generally raised at the foot of the east pyramid. The term "twin-pyramid complex" was first used in 1956 by Edwin M. Shook when he recognised that five such groups conformed to a similar architectural pattern.