If you're a very fast swimmer it could take you as little as 7 or 8 hours to swim the Channel but if you're a slower swimmer it can take as long as 27 to 30 hours to swim the Channel.
Swimming the Channel is a difficult but not impossible thing to do and if you were able to swim the Channel it would be a great thing.
The First person to ever swim the Channel and complete the swim of the Channel was Matthew Webb, who swam breast stroke.
Matthew Webb swam the Channel in the year 1875.