The question is pretty self-explanatory. I'm just curious whether we know of any attempts to cross the Atlantic Ocean prior to the Columbus expedition. Or was he literally the first person we know of historically who sincerely proposed sailing across the Atlantic Ocean?

The only two instances I could find that might fit the bill are:

• Obviously Lief Erikson's attempts to sail across the North Atlantic, ultimately succeeding in reaching "Vinland" circa 1000 AD
• Vague rumors that Mansa Abu Bakr II of the Mali Empire had abdicated the throne in order to explore the Atlantic Ocean with a massive fleet in the 14th Century

I apologize if this has been asked before, I've searched around and haven't found any other threads on this topic.

EDIT: And to be clear, it seems completely obvious that any previous expeditions were not successful. I don't mean for this to come off as some sort of conspiracy theory about other groups landing in America before Columbus. Because it seems obvious that even if there were any previous attempts to cross the Atlantic, they weren't successful.