We've ridden the train 4 times now, most recently in August, 2013, either getting to or coming out from wilderness backpacking trips. The train runs from Durango to Silverton and back again, but we've always gotten on or off at the Needleton stop. Kids (and many adults, like my steam train-obsessed backpacking friend) absolutely love the puffing locomotives, the restored rail cars, even the smoke from the coal-fired engines. The train not only gives a glimpse into what travel in these mountains was like a century ago, it gives relatively easy access to some wild country. The route goes through some of the most rugged mountains in the US, and follows along the wild Animas River. Just beautiful.
Not sure on pricing, as we've always ridden one-way. I'll echo what others have said: if you really want to be in a coach car get your tickets in advance. This is a really popular activity in the area. By the day of, you might only find seats in the open coaches. I personally like these - I think the view is better - but the experience can be drafty and a bit wet if the weather is cool and/or damp. Or just take clothes for the conditions and make it all part of the adventure..
One tip if you DO ride the open cars. These engines burn coal, and there's a certain amount of soot in the smoke from the stack, which does drift back over the train at times. First time we rode the train out from a hike I was wearing a white base layer shirt. That shirt has never been white since. Dark colors hide the soot better.
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