Palma Sola is Acapulco's premier archaeological discovery which consists of ancient Indian petroglyphs (primitive cave drawings) that date back some 2,000 years to the pre-classical period. The area is exotic, located at the foot of a mountain, with lush vegetation on all sides and an excellent view of the bay. The site,featuring 18 stones, is still being studied by the Mexico's National Anthropology and History Institute (INAH). The site is worth a visit for the ecotourists and history buffs among you, since as the drawing are believed to have been made by the first inhabitants, the Yopes, about which little is known. There is no cost to visit the site and arrangements can be made a Fort San Diego. The site is open to visitors daily 9 am to 5 pm.