After the British company Castle had bought the rights for the TD back catalogue of 'The Blue Years' era, they had re-released those albums in 1996. Two years later they released the additional compilation The Blue Years, including some tracks from these albums, compiled by Edgar Froese himself:
In opposite to the compilation Book Of Dreams, released by Castle in 1995, this CD contains the un-remixed original tracks as they are featured on the regular Castle CDs with the exception of Vigour that was not included on the CD re-release of Tyger. Together with The Pink Years, a compilation of tracks from 1970 to 1973, The Blue Years CD gives an overview of TD's pre and post Virgin years. This compilation contains no new material.