
The birth of a concrete giant
The secret code of the roads
The heavy toll of progress
Life in the fast lane
YOUR GOAL
Master of The interstate highway system

sloane Steer runaway trucks into escape ramps to learn how interstate design prevents mountain disasters.
sloane Interstate Highway Numbers
If the Interstate starts with an odd number, It's a spur, but an even one's a loop, you discover!

sloane Strict engineering standards like wide lanes and controlled access made interstates safer than older highways.

sloane Three-digit interstate numbers identify bypasses, spurs, and loops around major metropolitan areas.
Mile marker zero: Most interstate mile markers start counting from the south or west border of each state.
What is the main design feature that distinguishes an interstate from a regular highway to ensure high-speed safety?
Why do engineers often choose concrete instead of asphalt for busy urban interstate highways?
What safety feature is built on steep mountain interstate descents to stop out-of-control vehicles?
What does a three-digit interstate number starting with an even digit, like I-495, represent?
In the US interstate numbering system, which direction do odd-numbered highways like I-5 and I-95 run?
Where would you find the lowest even-numbered interstate highways, such as I-10, in the United States?