I'm sure this is silly and won't be terribly difficult to answer: can one climb atop a mountain or is it proper to say climb on top of. Or does it matter? I'm thinking the latter is correct.
closed as general reference by Robusto, Mahnax, Kristina Lopez, John Lawler, cornbread ninja 麵包忍者 Jan 4 at 3:56
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I don't think you would do either of these to a mountain, you would simply climb a mountain. Otherwise, they're interchangeable but atop is less used. Humpty Dumpty might sit atop a wall, but most other people would sit on top of one.