A £71m project to revamp London's Royal Festival Hall has begun as part of a £90m programme to improve the famous music venue on the city's South Bank.
The Festival Hall will be given a complete makeover
Initial work began this week, but the main refurbishment of the auditorium and foyers will start in summer 2005.
Acoustics, amenities and access will all be improved - and there will be more leg room for concert-goers.
A new education centre is also due to be built on the ground-floor of the 53-year-old venue.
"The acoustic aspirations of the original designers were never fully realised," said Michael Lynch, chief executive of the South Bank Centre.
"Now we have the opportunity to complete the job, with the benefit of 21st century technology and with financial support from the National Lottery and from private donors and sponsors."
The South Bank Centre incorporates the Royal Festival Hall, the Hayward Gallery, Queen Elizabeth Hall and the Purcell Room.
The unfavourable acoustics in the current auditorium will be improved
Seating will be renovated in the Royal Festival Hall's main auditorium and air conditioning will also be improved.
A new extension between the railway bridges and Hungerford terraces is being created for administrative use, in order to free up public space in the Festival Hall.
The Hall's artistic programme will continue as normal until the major work begins next summer, when it will close temporarily.
Events will take place in the Queen Elizabeth Hall, Purcell Room and Hayward Gallery until the Royal Festival Hall reopens in January 2007.
Funding has come from a variety of sources including lottery grants and gifts and donations - £73m of the £90m needed for the Hall's transformation has been raised so far.
The £71m programme that has just begun will be spent on the Royal Festival Hall alone - the remaining £19m is to create the extension building and improve the area around the venue.