This is a beach that travel guides ignore but vacationers love. The only problem is Barra Vieja, in San Marcos, is about an hour's drive of Acapulco. Still, most say the trip south is worth the hassle of renting a car. One TripAdvisor traveler recounts horseback riding, massages on the beach and excellent ceviche: "I hesitate telling anyone about it," they add. "I hope it stays secluded."

Just one word of caution before you go: You'll have to rent a car, and it can be expensive. Plus, the U.S. Department of State warns tourists against traveling Mexico's roads at night or alone. We emphasize that Barra Vieja is best as a daytrip with buddies.