The $6.5 million redevelopment of Cronulla Surf Life Saving Club has begun with the demolition of a non-heritage section.
An excavator and Bobcat were at work on Friday.
The project is scheduled to be completed by the end of 2019.
The three storey building will be rebuilt with a range of new facilities, a lift and new entry.
The ground floor will include new boat, ski and board storage areas, female and male amenities and a gym.
Level one will have a new lounge, bar, terrace, kitchen, toilets and function room, while level two will feature a new entrance from Cronulla Park, office space, lift, lobby and mezzanine.
Formed in 1907, the club is one of the longest serving surf life saving bodies in Australia.
It is also the longest serving community organisation in Sutherland Shire.
Cronulla MP Mark Speakman said last year members and supporters had worked tirelessly to raise funds for the redevelopment of the heritage-listed building.
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