Which band headlined at the first Glastonbury Festival in 1970?

Glastonbury was heavily influenced by the hippie ethics and the free festival movement in the early 1970s. The first festival at Worthy Farm was the Pilton Pop, Blues & Folk Festival, mounted by Michael Eavis on Saturday 19 September 1970, and was attended by 1,500 people. Tickets were £1. The original headline acts were The Kinks and Wayne Fontana and the Mindbenders but these acts were replaced at short notice by Tyrannosaurus Rex, later known as T. Rex.

T. Rex were an English glam rock band, formed in 1967 by singer-songwriter and guitarist Marc Bolan. The band was initially called Tyrannosaurus Rex, and released four folk albums under this banner. In 1969, Bolan began to make a shift from basing his band's sound around an acoustic guitar to basing it around an electric one and shortened their name to T. Rex.

Glastonbury Festival is now a five-day festival of contemporary performing arts that takes place near Pilton, Somerset. In addition to contemporary music, the festival hosts dance, comedy, theatre, circus, cabaret, and other arts. Leading pop and rock artists have headlined, alongside thousands of others appearing on smaller stages and performance areas. Glastonbury is the largest greenfield festival in the world, and is now attended by around 175,000 people, requiring extensive infrastructure in terms of security, transport, water, and electricity supply.