A recent study has shown that ancient hominids living during the Chibanian era must have had a way to reach the Aegean Islands by sea. Archaeologists have found ancient artifacts on these islands in the Mediterranean dating back to before the known appearance of Homo sapiens.
In summary: humans must have already been able almost half a million years ago to cross large bodies of water without the help of land bridges.
If this theory is confirmed, it could change the way we think about the migration of human beings throughout history.

When did we start sailing the Mediterranean?
Difficult to answer. Boats have long been built of wood, a material that can hardly survive tens of thousands of years, let alone hundreds. For this we lack direct evidence of the first navigations, in the Mediterranean as elsewhere.
We only have artifacts, bones, stone tools that do not decompose and allow us to reconstruct the way the world has changed over many millennia.
Guided by the geologist George Ferentinos of the University of Patras in Greece, a team of researchers started from these elements to conduct the new analysis, published in the scientific journal Quaternary International (I link it to you here).
Aegean, cradle of sailors
The Aegean islands are considered one of the most beautiful destinations in the world. Made up of hundreds of islands, this archipelago stretches across the Aegean Sea between Turkey, Greece and Crete. The inhabitants of these islands date back to ancient times, as demonstrated by the discovery of artifacts dating back as far as about 476.000 years ago and associated with the Acheulean style, developed about 1,76 million years ago and linked to Homo erectus in Africa and Asia.
Many of these artifacts have been found in Turkey, Greece and Crete.
In the past, ancient humans were believed to have traversed the islands on foot during the ice ages, aided by lowering sea levels. To test this theory, Ferentinos and his team reconstructed the geography of the region, including the shoreline of the Aegean Islands some 450.000 years ago, using ancient river deltas as indicators of sea level and subsidence rates due to tectonic activity.

What did they find out?
Previous assumptions about the amount of water in the seas were wrong. In fact, about 450.000 years ago sea level was "only" about 225 meters (738 feet) lower than it is today. This means that there would still have been several kilometers of Mediterranean to cross to reach the nearest of the Aegean islands.
Don't be surprised, however. The same researchers present evidence that archaic humans already made sea voyages through Indonesia and the Philippines between 700.000 years ago and one million years ago. Studies that give a precise indication: the ability to navigate the sea is not an exclusive peculiarity of theHomo sapiens, but it was acquired in earlier times by our (and their) ancestors.
We will never be able to know all of our history: but in the future we will rewrite a lot of the one that is widespread today. OR we will invent it, But this is not the case.