Definition & Meaning of "springing line"

What is the "springing line"?

In architecture, the springing line is an imaginary horizontal line that connects the points where a series of arches or vaults begin to rise from their supports. This line helps define the overall layout and design of the arches, ensuring they align properly and maintain a consistent height. The springing line is important for the visual and structural harmony of a building, as it guides the arrangement of multiple arches or vaults, contributing to the overall architectural style and aesthetic.