The part of Atapuerca we saw was along the railway cut. In the late 1800s railroads were built to bring iron ore and coal to Bilbao. One of the feeder lines went through the Sierra de Atapuerca. In addition to the iron ore and coal, this spur may have also brought limestone for buildings, some possibly used to build the foundries and bridge arches constructed at the same time. The railway spur cut through the Sierra de Atapuerca was 15 meters deep. It exposed ancient caves that had collapsed. At the time their importance wasn’t realized. We visited the area along the railway cut which contains three important archaeological sites: Sima del Elefante, Galería-Covacha de los Zapazos complex and Gran Dolina.
Sima del Elefante (Elephant Pit) was dissected by the railway cut. It is a complex area due to the diverse way the sediments filled the site and the fact that it was cut through by the railway. The cave was named for a tooth thought to belong to an elephant that was found there. It turned out the the tooth belonged to a rhinoceros. Now you know why it pays to be cautious with your naming! Sima del Elefante contains the earliest cave occupation sites in Sierra de Atapuerca and is where the oldest human remains (at least 1 million years old) in Europe have been found. (According to the “Illustrated Guide to Atapuerca” which is licensed under Creative Commons so it doesn’t have a copyright date, but appears it was published in 2014.)
Galería complex is the middle site along the railway cut. It was the first to have excavations started (in the 1980s). Remains from Homo heidelbergensis were found here in 1976, possibly 500,000 years old. One part of the complex may have been a natural pit that was deep enough to kill animals that fell into it. Apparently there was a “back entrance” where carnivores and hominids could get in. The supposition is that the humans carved off legs of the fallen (and now dead) animals and took them back to another, safer cave. By doing this, they were able to grab some of the meat before the large carnivores and competitors got it. The other cave was more protected and they could defend, deflesh, and consume the animals. This other place is another part of the Galería complex and the herbivore bones found there are almost exclusively leg bones.
Gran Dolina was the final cave that we visited. The railway cut destroyed the outer part of this cave. This cave contains an instance of magnetic reversal 780,000 years ago which very effectively dates the layers above and below it. A magnetic reversal is when there is a change in the earth’s magnetic field – magnetic north and magnetic south change positions. I’m not sure how you spot this, but I know how you prove it (at a particular spot) and what it looks like microscopically. But digging in a pit??? Maybe you just know (from other things) that you might be getting close. At any rate, Gran Dolina also contained fossils from Homo antecessor. This discovery moved back the first human groups in Europe to 800,000 YBP. At the time of the find, it was believed that humans had been in Europe only since 500,000 YBP. (Only?).
There is a nice visitor’s center well before you go into the site. As Atapuerca receives more visitors, they are well positioned to handle the crowds. There are several topographical displays of the area: one showing the railway cut. The site is able to produce their energy needs with solar arrays, which should tell you something about the location – very much in the open.