What is as the crow flies?

"The phrase "as the crow flies" is an idiomatic expression used to describe the shortest distance between two points in a straight line. This is in contrast to the actual travel distance, which might be longer due to roads, paths, or other geographical features that require a more circuitous route. The expression is derived from the idea that crows, being birds, can fly directly over obstacles such as rivers, mountains, or buildings, and thus can travel in a straight line from one location to another.

In practical use, "as the crow flies" can often be applied when calculating distances using maps or GPS systems, giving a direct measurement of the space between two locations without considering any terrain or infrastructure. For example, if two towns are said to be "50 miles apart as the crow flies," that means they are 50 miles apart in a direct line, although the actual driving distance may be greater. This measurement can be particularly relevant in contexts such as aviation or planning for outdoor activities like hiking.

Overall, the phrase has come to be a useful metaphor for measuring direct separation and is commonly used in both casual and technical communication.