South of Tulum, Mexico's Highway 307 turns away from the Caribbean and plunges into the jungle. Green walls of jungle encroach on the shoulderless ribbon of pavement that stretches from the hustle-bustle of Cancun to the remote Belize border. As we drive through this leafy tunnel, nothing is visible but a straight line of asphalt ahead and a stripe of blue sky above. We pass a large family on bicycles— jet black hair framing broad copper faces. They ride three to a bike.

Farther south, the trees and vines abruptly recede, revealing occasional clusters of stick-walled, thatch-roofed huts. These tiny villages are marked by jarring topes, speed bumps made of concrete or thick-as-a-thigh ropes stretched across the road. Although we see no other vehicles for miles, entrepreneurial women and children are waiting each time we slow to cross these hurdles. They politely approach our car, offering bags of oranges, mangoes, or tortillas.

My husband Alan, our four-year-old twins, my mother, and I are headed for Rancho Encantado, a cottage resort in the tranquil, undeveloped southeast corner of Mexico's Yucatan peninsula. Rancho Encantado overlooks 40-mile-long Laguna Bacalar, the Lake of Seven Colors, whose mix of fresh and salt waters transforms its surface into a spectrum of blues. Located 200 miles south of Cancun but worlds from its high-rises and tour buses, the Bacalar region— gateway to recently-excavated Mayan ruins discovered from the Caribbean west toward Campeche— offers numerous opportunities to explore Mayan culture, past and present.