The large city of Yaxchilán (the name means “green stones”) ruled the Usumacinta River valley in what is now the state of Chiapas, Mexico . At one point Yaxchilán was a major rival of Palenque , Piedras Negras  (40 km down river), and Tikal .
The city is known for its gorgeous views down the river, and for the detailed sculpture and well-preserved wooden lintel carvings above the temple doors. The sheer quantity of hieroglyphic writing found here has given Yaxchilán a reputation for being “a treasure trove for epigraphers.”
Yaxchilán boasts the best-named founding father ever: Yat B’alam (Jaguar Penis), who took the throne in A.D. 320. The most important ruler of Yaxchilán, however, was Izamnaaj B’alam (Shield Jaguar), born in A.D. 647.
Izamnaaj B’alam ruled for 60 years and built an enormous monument for his wife, Lady Xoc. Structure 23, on the main plaza, is the only Maya structure known to have been built for a woman. Look for the carved panel featuring Lady Xoc passing a thorn-studded rope through her tongue in blood ritual.
There is some Long Count evidence at Yaxchilán. On the ball game panels under Temple 33 are some particularly deep Long Count texts—longer even than the 13 b’aktun cycle. The earliest important date written at the site is A.D. 435; the latest is A.D. 808.
Thirty kilometers (19 mi) south of Yaxchilán lies Bonampak, a separate site atop a beautiful ridge. It is famous for its brilliant color murals, painted around A.D. 800. Scenes depict a great, bloody battle in A.D. 792 and are fantastic for their detail, especially those located within Structure 1 (The Temple of the Murals). A full-scale reproduction of the temple is in the National Museum of Anthropology and History in Mexico City.
Bonampak is included in most tours to Yaxchilán.
Yaxchilán is open 10 a.m.–5 p.m. daily, but accessible only by boat. Entrance is US$5. Team up with a tour company or find a boat service in the town of Frontera Corozal. After docking at the site, visitors enter a tunnel under Edificio 19 and emerge into the Grand Plaza. Instead of following the main path, climb to the Little Acropolis and work your way downhill through the ruins.
Most people visit Yaxchilán and Bonampak as a combined trip after touring Palenque , a four-hour drive down the river valley. Bonampak Archaeological Park is open 8 a.m.–5 p.m. daily. Entrance is US$10. There are basic services and refreshments at the visitors center.
The border town of Frontera Corozal was founded in 1976 by Ch’ol Maya immigrants from Guatemala and has some basic services, including boats and guides, a museum, restaurants, and accommodations like Escudo Jaguar (tel. 502/5353-5637, www.escudojaguarhotel.com , US$20–60).
This is the best part: Yaxchilán can only be reached by a 25-kilometer lancha (boat) ride (45–60 min., US$65 for 1–3 passengers) from the village of Frontera Corozal .
By combi from Palenque , buses leave hourly 5 a.m.–5 p.m. (US$7). By car from Palenque, take the Carretera Fronteriza approximately 100 miles to Crucero Corozal. From there, drive 13.5 miles to Frontera Corozal.