It held that name back when it was a major highway. It's not a particularly dangerous road by the standards of the region. The other commenters is right that

It held that name back when it was a major highway. It's not a particularly dangerous road by the standards of the region. The other commenters is right that the name comes from the prisoners who died building it. Allegedly they were buried in the road. I say "allegedly" because everyone who's ever built a road knows that the road base is key to longevity and that adding things that will decompose to it is the opposite of what you want to do.