Similarities between Neanderthal tools in Siberia and eastern Europe suggest Neanderthals crossed the Eurasian continent about 60,000 years ago - 40,000 years after an earlier migration.
     Unlike the more famous Denisova Cave which was occupied at various times over about 250,000 years by Neanderthals, anatomically modern humans, and Denisovans, the Chagyrskaya Cave 100 kilometres to the west in the foothills of the Altai Mountains seems to have been occupied only by Neanderthals. There archaeologists have found 74 Neanderthal bones - the most of any cave in the region - as well as around 90,000 artefacts including stone and bone tools.
     More than 3,000 stone blades from the cave resemble flaked stone tools from Central and eastern Europe known as Micoquian blades, suggesting the Neanderthals who occupied the Chagyrskaya Cave descended from groups more than 3,000 kilometres to the west who may have been following migrating herds of bison or horse through central Asia.
     Some geneticists have previously suggested that Neanderthals migrated to Siberia twice, because late Neanderthal occupants of the Denisova Cave are more closely related to their European relatives than to the cave's earlier occupants.

Edited from Cosmos Magazine (28 January 2020), Smithsonian Magazine (29 January 2020), The Siberian Times (30 January 2020)