204+ years after the fact? New Vegas did it right, with radiation having been severely dissipated or gone in most places completely. Even a place that got multiple nuke detonations, would be rather calm 204+ years later.
Raiation could last for thousands and thousands of years. I wouldn't be so sure the radiation would be gone.
And I'm not saying the whole map or anything, I'm just saying like a small secluded area away from settlements and stuff.
Besides, in new Vegas wandering into a garbage site or even vault 34 or nuke test site can kill you from radiation in a few seconds, so yeah. Just apply that in a small area(like city but ruins) and wallah.