WSL paths in Windows

Windows Subsystem for Linux (WSL) allows you to install Linux distributions such as Ubuntu under Windows. The root filesystem you see under WSL is located at a directory inside %LOCALAPPDATA% in Windows.

For example, the root directory of Ubuntu 18.04 can be located in Windows here: %LOCALAPPDATA%\Packages\CanonicalGroupLimited.Ubuntu18.04onWindows_79rhkp1fndgsc\LocalState\rootfs