Oystermouth Castle in Mumbles, near Swansea, is set to undergo an extensive £1.7m restoration project following a cash injection from a number of funding bodies.
Half of the historic attraction is currently closed off to the public due to disrepair, and it is hoped that 95 per cent of the site will be opened when work is completed.
Swansea Council has contributed £569,000 towards the scheme, as well as £800,000 from the Heritage Lottery Fund (HLF) and £400,000 from Cadw, the historic environment service of the Welsh Assembly Government. The Friends of Oystermouth Castle (FOC), a group of volunteers who manage the day-to-day running of the castle, will also provide £6,000.
Plans for the castle's restoration include conservation work and the construction of a new visitor centre in the castle's disused chapel block. It is hoped the project will increase visitor numbers to the site from 6,000 to 11,000 by 2011.
Roger Parmiter, chair of FOC, said: "There's great affection for Oystermouth Castle among local people, and this funding news is the single most important event in the 150 years of the castle's recent history."
Five years ago, a Cadw report described the castle as being in the worst condition of any open to the public in Wales, and said that it faced inevitable closure without restoration.
Dan Clayton Jones, chair of the HLF committee for Wales, said: "Without this funding, we would undoubtedly lose Oystermouth Castle, which would not only mean the demise of a significant local historical asset, but also the vital community engagement which has kept the castle alive over recent years."