The premise/intention behind this scheme is as follows:
- Replace the overlapping I- and US- highway numbering systems with a single federal highway numbering system
- Highways should designate the "best" route between points along its path. Routes shall pass through or bypass cities, as appropriate. For example, an I-65 equivalent would pass through Indianapolis, but an I-70 equivalent would follow I-270 around the north side of St. Louis.
- I don’t care about conflicts with existing state highway numbers.
- The same number set will be used regardless of highways’ status. However, both alpha-suffixes and shield colors will be used to designate different highway classes.
- Extended multiplexes (e.g. I-70/I-76, I-80/I-90, I-39/I-90/I-94) are to be avoided.
- Numbering inconsistencies caused by routes crossing one another (e.g. part of I-77 being east of I-81) are to be minimized (or avoided, if possible).
- The numbering system is designed for US use, but could be extended into Mexico and Canada for a true NAFTA highway system.
- Space should be left in the numbering scheme for future expansion or upgrades. (E.g., there should be no need for out-of-sequence I-67 and I-99 in Pennsylvania.)
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