How many people have been to the dark side of the moon?

First of all, there is no part of the moon that stays dark all the time. Half of it is dark

at any instant, but that 50% keeps moving, just like it does on earth, and creeps all

the way around the moon every 27.32 earth-days.

Now, to the question and its answer:

For every Apollo mission that had any possibility of landing on the lunar surface, the

landing site was carefully planned to be in the illuminated portion of the surface, but

close to the "terminator" ... the line where darkness began ... so that the shadows

at the landing site would be relatively long, and the astronauts would be able to

maintain their bearings as they hopped or drove around.

So the short answer to the question is: Zero.