Contour Maps

Reading a landscape

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• A function $f(x, y)$ can be pictured as a landscape.
• Contour lines join points of equal height: $f(x, y) = c$.
• Close contours mean steep ground. Far-apart contours mean gentle ground.

Steps

1. Height as a function
2. Steep or gentle?
3. A bowl
4. A saddle
5. Reading the gradient
6. A mountain pass