To measure a road that is not straight ... we could then calculate its real length using the scale. If the map scale is 1:25000, we could first work out the length in cm, then convert to metres ...

Ebrahim, Alnoor, and V. Kasturi Rangan. "What Impact? A Framework for Measuring the Scale & Scope of Social Performance." California Management Review 56, no. 3 (Spring 2014): 118–141.

The meter is the base unit of length in the International System of Units (SI), making the nanometer a derived unit used primarily to measure the atomic and molecular scale of materials and the ...