From c. 100 B.C. to A.D. 1300, the Sier­ra de San Fran­cis­co (in the El Viz­caino reserve, in Baja Cal­i­for­nia) was home to a peo­ple who have now dis­ap­peared but who left one of the most out­stand­ing col­lec­tions of rock paint­ings in the world. They are remark­ably well-pre­served because of the dry cli­mate and the inac­ces­si­bil­i­ty of the site. Show­ing human fig­ures and many ani­mal species and illus­trat­ing the rela­tion­ship between humans and their envi­ron­ment, the paint­ings reveal a high­ly sophis­ti­cat­ed cul­ture. Their com­po­si­tion and size, as well as the pre­ci­sion of the out­lines and the vari­ety of colours, but espe­cial­ly the num­ber of sites, make this an impres­sive tes­ti­mo­ny to a unique artis­tic tra­di­tion.