Fred - just spent a couple days exploring the lower east side, and was able to get into Lava, then up to Whiplash, Big Horn, Sublette. I used USGS 7.5 topo maps (my older Topo USA copy was not very useful). Most of the roads were as marked, but the Antonito section is dated 1967, so there are some changes! As you get farther into the boonies, good clearance is needed (My 2001 Jeep Cherokee was fine). Many of the grade crossing had no dirt for the road, so it was up-and-over. Most roads are public, but always leave the gates as you find them. I'm sure that others will more experience can elaborate on details, but a lot of the fun is wondering if you'll have to walk back to town.
Steve
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