Piedras Negras (pyā'THräs nā'gräs) [Span.,=black stones], ruined city of the Classic era of the Maya, NW Petén, Guatemala, in the Usumacinta valley. Reaching a peak of sculptural achievement (according to one dating system, between 731 and 795), Piedras Negras developed some of the finest pre-Columbian stonework.




