Thanks to Epic Games, Unreal and Unreal Tournament games have appeared in the Internet Archive. This was reported by one of the representatives of the OldUnreal community.
Both games were withdrawn from sale many years ago, but with Epic's approval, they will live on as part of video game history.
Players can download the disk images directly from the archive(Unreal and Unreal Tournament) or use OldUnreal's previously released Windows installers (Unreal here, Tournament here) to install the patched versions. Currently, the installers are only available for Windows, but the OldUnreal team is working on Linux and macOS versions.
The series officially ended with the release of Unreal Tournament 3 in 2007. There was an attempt to revive the franchise on Unreal Engine 4, but later Epic focused on Fortnite and the series was officially shelved.