Sierra de San Francisco

The Sierra de San Francisco, north of San Ignacio, holds one of the most remarkable collections of rock art in the Americas, and since 1993 it has been a UNESCO World Heritage site. In rock shelters along deep canyons, ancient peoples painted human figures and animals, often larger than life: people with raised arms, deer, bighorn sheep, rabbits, birds, and even whales and sea turtles, in red and black and sometimes split down the middle in both colors.

The style is known as the Great Murals. The paintings were made over a span of thousands of years, and when the Jesuits arrived in the 18th century, the Cochimí told them they were the work of a race of giants who had lived there before them.

The easiest site to see is Cueva del Ratón, a short walk from the road near the mountain village of San Francisco de la Sierra, named for a figure once taken for a rat that is probably a puma. The most spectacular murals, such as Cueva Pintada in the canyons of Santa Teresa and San Pablo, are reached only on multi-day trips by mule with local guides.