AbstractColor measurements were carried out in September, 1981, and again in January, 1982, on a total of 102 color zones in 12 different figures in the polychromatic roof of the Paintings Room of the Altamira Cave. The comparative study was carried out to evaluate any seasonal variations in reflectance and color between these two months, in which the humidity of the rock base for the paintings differs widely. No differences outside of experimental error were found.