Archaeologists found ancient cave are in northeastern Mexico and revealed that thousands of ancient cave paintings were discovered located on the walls of caves created before the time of Spanish rule.
The ancient paintings were found in the area surrounding the Sierra de San Carlos, a mountain range in Mexico's state of Tamaulipas, according to researchers.
Nearly 5,000 cave painting have been found and documented in 11 different sites throughout the area, researchers said.
The paintings were comprised of red, yellow, black and white colors and the paintings depict various animals such as deer, lizards, centipedes and people.
There are also various actions painted, such as characters hunting and fishing as well as what is thought to be astronomical charts.
The findings show pre-Hispanic groups, "where before it was said that there was nothing, when in fact it was inhabited by one or more cultures," archaeologist Gustavo Ramirez, of the Mexican National Institute of Anthropology and History, said in a statement.
The ancient civilization depicted in the paintings left few artifacts behind and there is little known about the people who lived on the mountains of Tamaulipas such as their languages, rituals and customs.
Another archaeologist, Martha Garcia Sanchez, said these people were able to resist Spanish rule by living in the mountains, "where they had water, plants and animals to feed themselves."
The rock art was rediscovered in 2006, and archaeologists first started studying the site two years ago. Further analysis should be able to more accurately date the artifacts.
"We have not found any ancient objects linked to the context, and because the paintings are on ravine walls and in the rainy season the sediments are washed away, all we have is gravel," Ramirez added.
The findings were recently presented during the Second Conference of Archaeological History in Mexico City.