It's not all good news - Deacon Blue are playing too...
The Big Weekend, on the Civic Centre lawn close to Cardiff Castle, traditionally features a long line-up of Welsh bands and unusual national acts.
August 4 and Deacon Blue will close the event on August 5.
It will be Gorky’s first show since their well-received tour of small Welsh venues in the spring.
All the gigs are free admission, with no ticket required. More bands will be added in the coming weeks.
A “Big Buzz” live open-air event has also been confirmed for Cardiff Bay on July 26, as part of the city’s annual festival. No acts have yet been confirmed.