Campaigners who are battling to restore Saltdean Lido have been promised £4.7m by the Heritage Lottery Fund.
The money will help reopen the historic Grade II* listed building which is currently on the English Heritage at Risk Register.
The Lido restoration will help rejuvenate the town and will prove a big attraction for residents from across Sussex.
Chair of Saltdean Lido Community Interest Company (CIC) Rebecca Crook said: “The backing of HLF has always been central to the success of our project and we are delighted that all our hard work is coming to fruition.
“The Saltdean Lido CIC will be creating new jobs and bringing new revenue and much needed investment to the area.
“However, there are many challenges for community groups such as ours who are bringing heritage buildings back into use.”
This funding will enable the CIC to renovate and revitalise the entire site, bringing both the iconic 1930s building and pools back into use.
It will transform the site into a modern leisure destination providing the local community with: a heated outdoor pool, indoor and outdoor play areas, café, gym, community and function rooms and a revived library.
The CIC said the closure of the lido and its sister building, the Ocean Hotel, had a negative impact on the economic health of Saltdean.
But reopening and renovating the lido would act as a catalyst to regenerate the area.
Heritage Lottery Fund historic environment advisor Ben Greener added: “When it was built, Saltdean Lido was the beating heart of a successful seaside resort.
“Sadly, as the lido declined, so did Saltdean. Yet local people never forgot how important this heritage icon was to their town.
“Now, through Heritage Enterprise, the Heritage Lottery Fund is enabling the community to find a sustainable solution for this precious local landmark, signalling Saltdean’s return to prosperity whilst saving one of the most significant lidos in the UK.”
Situated just four miles along the coast from Brighton the Lido was designed as the centrepiece of Saltdean’s new seaside resort and first opened in 1938.
Comprising an iconic Art-Deco building and three pools, it was created to elevate Saltdean’s status as a fashionable resort in the competitive 1930s British holiday market.
After just three successful seasons it closed in summer of 1940 and did not reopen to the publicagain until 1964.
During the Second World War the National Fire Service used the pool as a water tank and its ground for training.
The onset of war halted Saltdean’s development and so in the years after, the Lido’s changing rooms were sanctified and used for church services and a Sunday school.
With the exception of the council run local library and a number of small-scale commercial activities in a 1960s extension, the site has been vacant since 2011.