Numbering rules
Place any interstate on the grid. Items you miss come back fast; items you nail decay to days.
Where does I-? run?
How the bands work
- East-west (even): ≤20 = south band (I-10, I-20), 30–60 = middle (I-40, I-70), ≥70 = north (I-80, I-90).
- North-south (odd): ≤25 = west (I-5, I-15, I-25), 35–65 = central (I-35, I-55, I-65), ≥75 = east (I-75, I-81, I-95).