`` Led Zeppelin '' released the album `` Led Zeppelin '' in 1968 .
Although the group was initially unpopular with critics , they achieved significant commercial success with albums such as `` Led Zeppelin '' , 1968 , `` Led Zeppelin II '' , 1969 , `` Led Zeppelin III '' , 1970 , `` Led Zeppelin IV , 1971 , `` Houses of the Holy '' , 1973 , and `` Physical Graffiti '' , 1975 .
Led Zeppelin