Some Yellowstone visitors
Else clues• Appalachian Trail enthusiasts
• Backpack toters
• Backpackers
• Foot travelers
• Many national-park visitors
• Nature-trail travelers
• Ones on trails, perhaps
• Parkgoers with backpacks
• Path finders
• Range rovers
• Some park users
• Trail followers
• Trail travelers
• Trail trekkers
• Trail walkers