Learn the interstate system
Spaced-repetition quizzes over the numbering rules, hub junctions, and route building.
Today's review
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East-west trunks (even, south → north):
North-south trunks (odd, west → east):
1. Numbering rules
Even = east-west, odd = north-south. Low = south/west, high = north/east.
Start →2. Hub cities
Atlanta is I-20/75/85. Dallas is I-35/20/30/45. Know the junctions, routing falls out.
Start →3. Build a route
Given two cities, type the interstate sequence. The map animates each segment.
Start →