What was the name of Apple's corporate headquarters before Apple Park?

Before Apple Park, Apple’s corporate headquarters was known as Infinite Loop.

More precisely, the headquarters was the Apple Campus at 1 Infinite Loop in Cupertino, California. The name “Infinite Loop” came from the private circular road surrounding six buildings, whose addresses ran from 1 Infinite Loop through 6 Infinite Loop. Employees commonly shortened the campus name to “IL.”

The site opened in 1993, but it was initially used mainly for research and development while Apple’s headquarters remained elsewhere. After Steve Jobs returned in 1997, the campus became Apple’s official headquarters and the buildings were renamed from R&D designations to Infinite Loop numbers.

Apple Park, originally called Apple Campus 2, began replacing Infinite Loop as the company’s main headquarters in 2017. Infinite Loop did not disappear: Apple continued using it for offices and laboratories. Therefore, “Apple Campus” is the formal campus name, while “Infinite Loop” is the canonical quiz answer.