Conversation so far:
when did horslips return?
In March 2004.
Where had they been?
CANNOTANSWER.
what did they do after they returned?
Horslips returned to the studio in Westmeath to produce a studio album, Roll Back, in the summer of 2004.
was the album a hit?
CANNOTANSWER.
Are there any other interesting aspects about this article?
The exhibition moved to Belfast in February and March 2006.

Question: what exhibition was there?
Self-contained rewrite: what exhibition was there for Horslips' return