Guerrero Negro, located halfway down Mexico's Baja Peninsula, is visited for mainly one reason—it's near Parque Natural de la Ballena Gris (Gray Whale National Park). January-March, gray whales breed and give birth to their calves near the shores of Laguna Ojo de Liebre (also known as Scammon's Lagoon). Take binoculars if you go there and pay the small fee for one of the boat tours—it's worth it to get out closer to the whales.

Another destination in the area is San Ignacio (a small oasis town 90 mi/145 km to the southeast) and the nearby San Ignacio Lagoon, home of the "friendly whales." For whatever reason, many of the whales there seem better disposed toward humans, and some will even swim close enough to be petted.

Santa Rosalia, 43 mi/70 km farther east, is a tiny town that features a prefabricated church designed by Alexandre Eiffel of Eiffel Tower fame. Between this town and Guerrero Negro, be sure to visit the cave paintings of Sierra de San Francisco, produced by the nomadic Cochimi before the arrival of the Spanish.

Puerto San Carlos on Magdalena Bay (farther south on the peninsula) is another great spot for whale-watching. Local tours are available. There are also cave paintings nearby, accessible only on horseback.