Mac OS X Lion (10.7), released in 2011, is a legacy, unsupported operating system that can be officially downloaded as a .dmg file from Apple. For installation, this file is often converted to an ISO or used to create a bootable USB to bypass modern security certificate errors and server limitations. For the official download, visit Apple Support. How to Create a Bootable USB Installer for Mac OS X Lion
While Apple originally distributed Lion via the Mac App Store and later on USB thumb drives, it is now available as a free download for older systems. mac os lion iso
The download from Apple is a .dmg that contains a .pkg installer. You need to extract the actual system image (InstallESD.dmg) to create a bootable ISO. Double-click the downloaded Mac OS X Lion.dmg to mount it. Mac OS X Lion (10
Unlike previous versions of macOS (which were sold on physical DVD discs) and subsequent versions (which are downloaded via the App Store as invisible background updates), Lion was the first macOS to be distributed primarily digitally. How to Create a Bootable USB Installer for