Roads – how to represent evolution?

[Minh_Nguyen]

Oh, you’ve structured this more deeply than I would’ve anticipated. Do I understand correctly that each of these superroutes represents the entirety of US-24 during a given time period, while each of its member route relations represents a section of the route that shares the same history? What I normally do is skip the subrelations and flatten them all into a single level of route relations:

• US-24 chronology relation
  • US-24 from 1961 to 1969 route relation
    • West Colorado Avenue highway way

That way, I can add an additional level for westbound versus eastbound, handy for the freeways that I more frequently map:

• US-24 chronology relation
  • US-24 from 1961 to 1969 route relation
    • Westbound US-24 from 1961 to 1969 route relation
      • West Colorado Avenue highway way
    • Eastbound US-24 from 1961 to 1969 route relation
      • West Colorado Avenue highway way

What you have is fine, since technically a route relation can be split up and nested an arbitrary number of times, but don’t feel obligated to do it every time you map a highway route. That must’ve been mind-bending!