http://mentalfloss.com/article/65859/10-american-ghost-towns-you-can-visit
I've been to the Bannack one. Really cool. Montana turned a mining ghost town (and surrounding land) into a state park so as to preserve it.
In the link, there's apparently another ghost town in Montana, Garnet, that is beauro land management owned. I didn't know of that one. Blm has a lot of open hunting land that's great for antelope and good for elk. Other states, public hunting land is mostly a joke. Montana and its people are pretty cool all around. Missoula has too many displaced California hippies tho.