Mississippi could point to the general region of the US on where to find Lake Powell. Not that they've never heard of it (though a lot will have never heard of it, or at least the name will have never sunk into their minds), but that it's a lake they've never been to, never going to, it's out of sight, out of mind.
I think most people when they think of Utah they know Mormons, Salt Lake, there's mountains, and perhaps Park City (though it wouldn't surprise me to learn if some people think Park City is in Colorado simply because they don't associate it with Mormons). Outside of that, it would be a surprise to them.