Premise: Led Zeppelin II . Recording sessions for the album took place at several locations in both the United Kingdom and North America from January to August 1969 . It has been described as the band 's heaviest album . Led Zeppelin II was a commercial success , and was the band 's first album to reach number one on charts in the UK and the US .
Hypothesis: Led Zeppelin II is an album.
Label: ENTAILMENT