This is from the album 666, the 1972 double-vinyl monster that would break up this Greek band. Vangelis was working with different singers, Demis Roussos was doing solo work and the album was a huge departure from their earlier work. Much more progressive rock, weird lyrics, thematic and less approachable. It was almost entiely the work of Vangelis and the rest of the band did not like it, they wanted to play pop.
Aegean Sea is a slow motion, dreamy, cosmic rock-track, with weird lyrics and some great spacey guitar solos. It has a perfect late afternoon, sunny feeling.