One theory what led humans to move north into Europe?

According to the Smithsonian magazine, there are two major theories that try to explain how humans entered Europe. The first one claims that humans arrived in Europe through Turkey by the Danube corridor then followed into eastern Europe or like the second theory claims they went from Northern Africa to the Mediterranean coast.

The first theory has more support because a study published on the National Academy of Sciences of the US dated human occupation in a Lebanese cave 45 thousand years ago.