Milwaukee Railroad is a 1.9 mile heavily trafficked out and back trail located near Butte, MT that features a cave and is good for all skill levels. The trail is primarily used for hiking and is accessible year-round. Dogs are also able to use this trail.
What I liked about the trail is that it is more than an in and out. One can simply keep walking.. There are other trails which connect/cross so one can make a big loop as well as add distance. The railroad trail itself is easy. The dogs also had a great time. In the winter the entrances are blocked, but one can walk in from the roadside parking lots which adds to the distance. The park was not overly crowded the few times I went before the "official" opening of the season. Great scenery.
Its a nice easy trail that is only about 10 minutes outside of Butte. The trail has an easy climb most of the way with switchbacks before you get up to the railroad.