The collection of rock paintings in the Muntanyes de Prades is made up of around forty archaeological sites, only three of which are open to visitors: Portell dels Lletres, Mas d'en Llort and Mas d'en Ramon d'en Bessó.
 
The compositions and pictorial scenes preserved here show hunters and wild animals such as goats, deer, bovines, or wild boars, as well as herders with domesticated animals and a large number of abstract signs and symbols. They depict the transition from hunting and gathering (simpler language) to agriculture (more complex language).
 
This may also have been a space for solar worship: in addition to the hunting scenes, we can see depictions of honey harvesting and sunsets.
 
in order to facilitate the interpretation of all these paintings, the Rock Art Interpretation Centre of the Mountains of Prades was created in Montblanc. It presents a significant sample of these prehistoric images as well as an exhibit with full-sized reconstructions of the rock shelters where they are found.
 
Some of these archaeological sites (around fifteen) were included in the UNESCO World Heritage list in 1998 together with the other rock art sites in the Mediterranean Basin of the Iberian Peninsula. They are also included in the Rock Art Route.