Bristol's Colston Hall concert venue has announced plans for a £45m transformation.
Works planned for the 1860s building centre on a new larger stage, new balconies, seating and acoustics.
The original Victorian windows will also be brought back into use and the cellars will be converted into studios and workshop spaces.
Building work is expected to begin in 2017 - the hall's 150th anniversary - and be completed by 2019.
This latest work is phase two of a project which began in 2007 and has already seen a £20m foyer built with a distinctive copper frontage.
The plans will see the existing main auditorium remodelled and the second hall, known as The Lantern, redeveloped into a performance venue.
The cellars, which are underneath the auditorium, will be opened up for the first time in 100 years to create educational workshops, workspace for performing arts and a cabaret style performance area.
The trust which runs the venue aims to raise the cash through a new 'Thank You for the Music Appeal'.
Louise Mitchell, Chief Executive at Colston Hall said the work would bring a "much needed concert hall of international standard to the city and region".
Musician Jamie Cullum who has played at Colston Hall many times said it is "good to hear they are planning to modernise the venue and to such a high standard".
"I'm also delighted that the new facility will be more than just an entertainment venue, and will nurture future talent through education and the development of businesses related to the performing arts," he said.