If you're 6' tall and look out over the ocean at sea level (from the water's edge), the horizon is roughly three miles away from you
@UberFacts Do the eyes have to be on 6' height or the whole body?
@UberFacts How tall do you have to be to see the ice walls around the edge of the earth?
@OnTheSpot2020 @UberFacts No further. But this 3 miles thing seems to be a bit short.
I can see boats that are a much further distance (I can tell the distance thanks to some islands), although I don't see the boat's floating line because of the planet's curvature. I guess that's the point here.