Piedras Negras, Maya archaeological site in Petén, Guatemala.

Piedras Negras is a ruined Maya city on the north bank of the Usumacinta River in Petén, Guatemala, built into a series of hills above the river. It covers about 4 km² and holds two acropolises, four plazas and two ball courts, with vaulted palaces and temple pyramids, one linked to a cave. A large boulder on the riverbank carries the emblem glyph of Yo'k'ib' facing skyward.

The settlement began around 700 BC and remained occupied until roughly 900 AD, with its peak activity during the Late Classic period. It served as an important trading and administrative hub along the river corridor.

The Maya people called this place Yo'k'ib, meaning 'great gateway' in their language. Stone monuments throughout the site display carved inscriptions that record stories of rulers and their lineages.

The ruins lie on the north bank of the Usumacinta in Petén, near the Mexican border, reached by river or by trails through the Sierra del Lacandón forest. There are no excavations under way today, so visits depend on guides and boats arranged in advance. The site is built into hills above the river, with plazas, two ball courts and two acropolises spread over about 4 km².

Artisans left their signatures through repeated glyphs carved into the monuments, providing visible evidence of individual Maya sculptors' names. These personal marks show a direct link between creator and creation that is rarely documented elsewhere.