calakmul is the biggest site, and its location in the forest preserve makes it doubly worth the long trek to get there. near calakmul are several other sites that can be visited more quickly, among them chicanná, becan, and xpujil.
closer to the coast are the eerie masks of kohunlich and the huge ceremonial site of dzibanché. adjacent to dzibanché are the temples of kinichná and several clusters of as-yet-unexcavated mounds. other sites in various stages of excavation that can be visited with a permit (obtained through a local guide such as those at rancho encantado) include el resbalon, chocchoben, and balam ku.
lamanai, a large site on the belize side of the rio hondo, is accessible by boat from mexico. -
tired of ruins? check out the white-sand beach of mahahual, an hour's ride by taxi or car from bacalar; the snorkeling is superb, and scuba diving even better. farther south in the bahía de chetumal, guided boat tours offer glimpses of the native manatee.
the museo de la cultura maya in chetumal is worth a visit for its scale models, precious artifacts, and explanations of the mayan calendar, astronomy, and math. the market across the street offers a slice of real mexican life; buy souvenirs or have a great mexican street lunch.