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Explore, research, conserve.

What is PRASBX

The San Bartolo-Xultun Regional Archaeological Project (PRASBX) is a multi-institutional collaboration engaged in archaeology, art conservation, and environmental science initiatives in Guatemala. PRASBX investigates two nearby sites in the northeastern Petén region that had a long history spanning the rise and fall of Classic Maya kingdoms (ca. 400 BCE – CE 900). San Bartolo has the earliest evidence of Maya writing yet discovered dating to the 4th century BCE and Xultun was an important city led by a powerful dynasty during the 5th-9th centuries CE. Today, the large urban center and its network of smaller sites have been reclaimed by tropical forest, a protected ecological zone designated the Maya Biosphere Reserve.

A new discovery at Xultun

Video “Sak Tahn Waax,” copyright 2026, Proyecto Regional Arqueológico San Bartolo-Xultun. All rights reserved.

SBX Project members Franco Rossi, David Stuart, and Heather Hurst have published a new decipherment of a text from the Xultun mural chamber, 10K-2. This study identifies the name of a Maya astronomer-mathematician for the first time: Sak Tahn Waax (White-chested Fox). Text 19 presents an elegant formula relating several units of time, including the 260-day ritual day-count, the solar year, as well as cycles of Venus and Mars, and concludes with the attribution “so says Sak Tahn Waax.” This eighth-century scholar’s work builds upon a millennium of observational astronomy and the text recorded at Xultun expresses the intellectual virtuosity of Maya mathematics and calendrics from a period with no surviving codices. This 3-minute video summarizes the discovery; the full text is available at Antiquity.

Our Impact

This Project is helping to protect and preserve these beautiful paintings, ensuring that future generations do not lose this knowledge and can see for themselves what our ancestors left us.

-M. J. T. from Sololá, Guatemala

Want project swag? …and to help us make new discoveries?

We have so many questions we would like to research, new sites we want to explore, and artifacts we need to conserve - please consider adding your support to our project. Our goals include researching newly discovered features identified using lidar, going solar in camp, creating more films and educational materials, additional tools for monitoring wildlife, and increasing student opportunities in lab analysis. SBX Project has amazing swag - check out our donation page through this link!