The remains of prehistoric animals from the Pliocene, an epoch between 5.3 million and 2.58 million years ago, near the Rhodope village of Dorkovo, were first discovered by a local teacher in the 1930s. In 1985-1987, a Bulgarian-French expedition surveyed the site only to realise that they had stumbled upon one of the richest finds of early Pliocene fauna in Europe and the richest one of Anancus arvernensis mastodons on the continent, including calves still with their baby teeth. 

About 3m tall and weighing up to 5 tons, these giants looked like modern elephants, but had much longer tusks reaching up to 3m in length. While mastodons are relatives of the more famous woolly mammoths, they are a different genus and became extinct much earlier, at the beginning of the following geological epoch, the Pleistocene.

In 2013, a special museum dedicated to the finds, was opened: a novelty for Bulgaria as it combined modern architecture and interactive displays.

The small museum is dominated by a model of a mastodon, an exhibit of real tusks (found not here, but around Yambol about 200 kilometres away) and of some fossils, a recreation of a paleontological excavation site and a 10-metre diorama recreating the habitat of these prehistoric animals. There is also a proper soundscape.

For more of Bulgaria's paleontological past, including the sight of the strange Deinotherium, which was related to elephants, and had backward facing tusks in its lower jaw, visit the Paleontological Museum at Asenovgrad (Badelema neighbourhood, 212th St), and the Museum of Paleontology and Historical Geology at Sofia University (main building, north wing, floor 5).