This chapter explores the archaeoastronomy alignments observed in the rock paintings at Serra da Lua and Serra do Sol, first documented in 2008. The investigation reveals that all known rock art at Ererê faces west, which is unique to this location, and concentric circle alignments correlate with the setting of the sun throughout the year, particularly during the solstices. Detailed observations show the constancy of these orientations over thousands of years, with evidence suggesting a relationship between the artwork and celestial events, influenced by local phenomena such as sun and moon halos. This implies the early artists had a profound understanding of seasonal changes. Ultimately, this research highlights the importance of horizon visibility and local geography in understanding ancient artistic expressions of astronomical phenomena.