What's Hidden There, one of the finest heavy progressive rock albums from faraway Iceland, remained the sole release by the short-lived four-piece band Svanfridur. Although the quartet played numerous live gigs in Iceland, they never secured a contract with an established record label. Apparently with a favourable offer from Majestic Studios in their pocket, they travelled to London in early July 1972 and recorded their debut album there from 11 to 18 July. It was self-released in a small run of just a few hundred copies and was appeared in September exclusively in Iceland.

Singer Pétr Kristjánsson, guitarist Birgir Hrafnsson, Gunnar Hermannsson on bass and Sigurd Karlsson on drums played a hippie-esque style of psychedelic rock, enriched with some folk elements and English-language lyrics. As well as complex vocal harmonies, the compositions are characterised by an original, inventive use of the Moog synthesiser, violin and flute, contributed by guest musician and arranger Sigurdur Johnsson. However, the private pressing on their own Svanfridur label sold poorly and vanished without a trace, leading to the band’s break-up as early as 1973. This extremely rare gem of early progressive rock is regarded as one of the most interesting examples of heavy progressive rock fused with influences from local folk music. And in great demand worldwide.