1.4 Map Scale and Distance

Notes

A map scale tells how distances on a map compare with real distances on the ground.

• A bar scale is a line marked in miles or kilometers. A verbal scale says it in words ("1 inch equals 50 miles"). A ratio scale uses numbers: 1:100,000 means 1 unit on the map is 100,000 of the same unit on the ground.
• A large-scale map shows a small area in great detail (a city). A small-scale map shows a large area with less detail (a continent).
• Worked example: if 1 inch equals 50 miles and two towns are 3.5 inches apart, the real distance is $3.5 \times 50 = 175$ miles.
• On a 1:100,000 map, 1 cm equals 100,000 cm, which is 1 km.