Yeah... Platte River trail is pretty flat. Runs along the river all the way.
I used to live way out west near Green Mountain (Almost to Golden) and there's a pretty easy route from there, as well... it's all on the roads, but they're all pretty lightly traveled... never really had any issues.
Personally I like the neighborhoods a little closer in... but I don't know what the schools are like.
Baker neighborhood is good, as is Athmar Park, Platte Park/DU area, Wash. Park, etc.
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