What architectural symbol became the defining visual mark of McDonald's restaurants?

The Golden Arches became McDonald's defining architectural and branding symbol.

Architect Stanley Clark Meston designed the arches for a McDonald's restaurant in Downey, California, opened in 1953. The large yellow structures stood at both sides of the building and were intended to make the restaurant visible to passing motorists.

The arches were initially part of the restaurant architecture, not simply a printed logo. Their shape later became an “M,” giving McDonald's one of the world's most recognizable corporate marks. The symbol was especially effective in the era of roadside dining, when restaurants competed for the attention of drivers.

The Golden Arches are sometimes incorrectly described as having begun as the modern standalone logo. In fact, their earliest use was physical signage and building design. McDonald's later simplified and standardized the symbol for packaging, advertising, signs, and corporate identity around the world.