About Interstate, the daily US highway game

Interstate is a free daily US geography game. Each day you get three highways, easy, medium and hard, like "I-35: Laredo, TX to Duluth, MN". The map shows only state lines and coastlines, with no roads, cities or labels. Trace the highway from one end to the other and score points for how close your ends are and how closely your line follows the real road. A perfect day is 1000 points: 250 for the easy round, 350 for medium and 400 for hard.

How interstate numbers work

US interstate numbers follow a pattern that helps you find them. Even numbers run east–west, rising from I-10 across the South to I-90 and I-94 across the North. Odd numbers run north–south, rising from I-5 on the West Coast to I-95 on the East Coast. The older US highways, like US 1, US 101 and US 20, count the other way: US 1 hugs the East Coast and low numbers run in the North. Some interstates come in two separate pieces with the same number, like I-84 in the Northwest and I-84 in the Northeast.

How to play

• Start at one end and draw the route to the other. Draw again to redo it, and drag either end of your line to fine-tune it.
• Zoom and move the map freely. A hint shows where one end is, for half of that end's points.
• After you submit, the real highway draws itself in. Compare your line with everyone else's, check the daily leaderboard, and share your score.

There are 68 routes, from coast-to-coast interstates like I-80, I-90 and I-10 to short regional ones like I-4, I-17 and I-99, plus classic US highways like US 101 and US 1. It's free, works in any browser, and has a new puzzle every day at midnight US Eastern time (9pm Pacific), the same moment for everyone.

Like maps? Try Contrail, the sister game, where you draw the curving shortest flight path between airports on a world map.

Ideas, bugs or a question? Email contrailgg@proton.me.