Windows 3.1 Download Options Windows 3.1 was originally distributed on floppy disks and is not "bootable" as a standalone ISO; it requires a pre-installed version of
Rufus is a popular tool for creating bootable USB drives:
Visitors often asked him whether they could download the OS images. Milo answered yes—but not with the blunt efficiency of a file server. He prepared a small guide for responsible preservation: notes on licensing, considerations about abandonware, and best practices for mounting images in virtual machines without endangering modern systems. He included a gentle note: files can be preserved; people cannot be reproduced. The archive’s mission was to maintain access while honoring the context in which these items had been meaningful.
: The go-to library for vintage software. They offer the original floppy disk images (IMG format), which you can use to install the OS manually on a virtual machine. Archive.org (Internet Archive)