Canyoning the Zimatan River Canyon near Huatulco, Oaxaca

Morning light finds the river slick and bright, the canyon walls throwing cool shade over the first steps. Guides clip harnesses and check helmets, voices low but sure. You move from dust to water in minutes—stones underfoot give way to polished bedrock and pools that dare you to jump. For roughly three hours the Zimatan River pushes the group forward: short swims, riverbed scrambles, and the muscle-work of balancing on boulders polished by decades of flow. The rest of the six-hour day is travel, a simple lunch, and a stop at La Bocana beach on the return.