Ayreonauts Only is the first compilation album by Dutch progressive metal project Ayreon by Arjen Anthony Lucassen, released in 2000. Although categorized as a compilation album, it consists only of previously unreleased material, with alternate versions of Ayreon songs with different singers, demos, and of the song "Cold Metal" from Lucassen's then-upcoming project Ambeon.

The album's name comes from the fact that, according to Lucassen, it is "intended primarily for die-hard Ayreon fans". It is notable for featuring vocals by Ian Parry and Leon Goewie, two former bandmates of Lucassen on his former band Vengeance.

The songs contained in the album are for the most part either demos or re-recordings of older Ayreon songs.

"Into the Black Hole", "Out of the White Hole" and 'Through the Wormhole" are three songs from Universal Migrator Part 2: Flight of the Migrator. For the first song, Lucassen wanted Bruce Dickinson from Iron Maiden; however due to Dickinson's busy schedule, it was unsure until the very last moment weither or not if he could come to Lucassen's studio and record it. As Damian Wilson came into Lucassen's studio to provide vocals in "And the Druids Turn to Stone" for Universal Migrator Part 1: The Dream Sequencer, Lucassen had the idea of recording a version of "Into the Black Hole" with Wilson, in case Dickinson would turn out to be unavailable. Dickinson was featured on the album version of the song, while the version present on Ayreonauts Only is the one with Wilson, and still features Lana Lane's backing vocals. For two other songs, Lucassen asked his friends Robert Soeterboek and Ian Parry (who had previously sung for him in Ayreon and Vengeance respectively) to provide guide vocals for the song's actual singers, respectively Timo Kotipelto and Fabio Lione; those guide vocals are the ones used in Ayreonauts Only.

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