Cobá

Once the most powerful Mayan city-state in the northeastern Yucatán, this 26-square-mile site, crisscrossed by raised limestone roads called sacbéob and home to three pyramids, remains relatively untouched by excavators’ hammers and tourist traffic. A highlight is Nohuch Mul, the Yucatán’s tallest pyramid; the distinctive architecture bears more of a resemblance to Guatemala’s Tikal than to neighboring ruins. Paths large and small make exploring easy.

Insider Tip: Plan your ascent of Nohuch Mul early or late in the day to avoid crowds and heat—sea breezes, coming from 26 miles away, don’t penetrate.