Scientists have dated a set of unique artifacts found in Kostenki, Russia to 45,000 years old—the earliest trace of modern humans in that region. They help clarify the route and timing of modern human migration from Asia to Eastern Europe.

The archaeologists found the artifacts in the layered walls of steep ravines at Kostenki. The team was able to date the artifacts because they lay beneath a layer of ash known to have been deposited in a volcanic eruption 40,000 years ago.

Because the style of the Kostenki artifacts is different from those found in Western Europe, the find supports the idea that different peoples first migrated to Europe along different routes. The artifacts’ age shows that modern humans likely reached Eastern Europe before they reached Western Europe.