Deep in the rain forest on the Guatemalan side of the Río Usumacinta, Piedras Negras Archaeological Zone boasts imposing tree-covered structures and magnificent sculptures and stelae, many signed by the artists who created them — a rarity in the Maya world. It’s also where the great Russian-born Mayanist Tatiana Proskouriakoff is buried; some of her most important breakthroughs, especially in deciphering previously unreadable Maya hieroglyphics, stemmed from her research at Piedras Negras in the 1960s.

Though quite isolated, Piedras Negras has gotten somewhat easier to reach, thanks to the construction of a new access road near Nueva Esperanza. Day-long excursions can be arranged through Valle Escondida (Carr. Fronteriza del Sur Km. 61, cell tel. 044-916/100-0399, busil_h [at] hotmail [dot] com); trips cost US$125 per person (four people minimum) and include round-trip transport, 2.5–3 hours at the archaeological site with a multilingual guide, and often a stop at the Cascada Busil-Há waterfall.