Archaeological explorations of this cave system were begun by Garcia Guinea in 1970, and continued between 1972 and 1987 under the guidance of Alfonso Moure Romanillo, who, with Rodrigo de Balbin Behrmann began to systematically record the imagery. In 2007-8 Balbin and Alcolea created a high quality digital record of the cave decoration and this enabled the discovery of unknown decoration and also an archaeological deposit containing crushed bone, teeth and shell mixed with ochre, in the gallery of the Anthropomorphs. This pigment has been dated to 32 990 +/- 450 BP (Beta 170181) (Balbin and Alcolea 2007-2008: 139). This highlights the great age of some imagery and hints at the symbolic significance of the use of pigments and the creation of cave decoration. The first two images seen appear to be human in form and have given name to this chamber of anthropomorphs. They are painted on to either side of a limestone formation known as a scarf stalactite. Uranium series dating which provides dates for the limestone formation on top of the painting means the painting is older than 29,600 and 25,200 years old. A sample taken by drilling into a recent break means the images are later than 33,500-37,700 years old. (samples 0-21 and 0-48)(Pike et al 2012).
Other radiocarbon dates that exist for images in Tito Bustillo are not as old as these Uranium series dates. If we consider all the C14 dates at the level of 95% accuracy then Bison 3 in Tito Bustillo sits within the ranges of 16831-15524 BP (GifA-96096) and 16755-15203 BP (GifA-96139). Horse 56 sits between the ranges 15104-14137 BP (GifA-96095), 14831-17872 BP (GifA-96098) and 18831-17872 BP (GifA-96144). Horse 58, which has four dates, ranges between 11230-10720 BP (GifA-96151), 17448-16154 BP (GifA-96149), 8388-8162 BP (GifA-96097), 17740-16925 BP (GifA-96142). Horse 39 dating between 13630-13306 BP (Beta-170179)and Horse 63 between 13226-12759 BP (Beta-170177) appear to be relatively consecutive. Although it is clear that some dates do not overlap or are far removed from the ranges of the other dates, all fit within the stages of middle to upper Magdalenian. (Dates after Balbin et al 2003 and Fortea 2002). All photographs were taken by Raquel Jiménez Pasalodos.