Here's where I think most Stone Age Europeans (Neanderthals and Sapiens) spent the winter
The light blue coastal areas on this map, along the northern shore of the Mediterranean Sea are just below present sea level, but were mostly exposed when the sea was low during the Stone Age.
During the Ice Ages, and especially during the cold winters, it must have been more hospitable near the Mediterranean Sea than in inland Europe. That's where I think most European humans lived. Scientists now know that fossil skulls of Stone Age European humans have exostoses, or 'surfer's ear' indicating that these people spent much time in rather cold water. They were probably living largely on marine foods, as their ancestors had on Bioko.
Evidence of coastal humans — their domiciles and art — has been submerged for the past 10,000 years.
But Cosquer Cave, just off the coast of France, is an example of a living area and spectacular art that was not completely destroyed. It was discovered by a diver in 1985.