I mean as far as traffic counts go (observationally, don't have actual numbers), the busiest roads in Spearfish are the business loop (North/Main/Colorado), Jackson Blvd, and the 27th/1st spur to Walmart. I guess that's what I was subconsciously basing that off of originally. As someone who grew up in the area (and has run on the non-existent shoulders #badidea), I would argue that 1st Ave, at least until the first entrance, qualifies as a "major road in an urban area". 