Lollipop's participation in the concert also marks, symbolically, the two-year anniversary of the group's formation.

This event also marked the 6th anniversary of the company's formation.

Cannibal Corpse have celebrated the 25th anniversary of their formation.

It was compiled to commemorate the group's 30th anniversary of their formation.

In 2012, marking the 56th anniversary of the group's formation, a touring exhibition visited galleries around Wales.

Bad Religion celebrate the 30th anniversary of their formation.

Album release was to commemorate the 10th anniversary of the band's formation.

Also in 2008 a number of former staff organised a reunion event to mark the 30th anniversary of the company's formation.

The band reformed to celebrate the 35th anniversary of their original formation.

This season marked the 125th anniversary of the club's formation in November 1885, which was celebrated in a number of ways.