The playground at South Hill in St Helier will be closed for almost three years.
The play area will shut at the end of the school summer holidays (7 September) while the Westward flats are being built on the site of the former Planning Offices.
Hoardings will be put up around the site to keep people away.
Jersey Development Company says it will replace the play area with a larger, modern and full inclusive one.
That is expected to open in summer 2029.
The Parish of St Helier said: "Although the playground will be unavailable during construction, the long-term result will be a significantly improved facility for the community."
Details of the design of the new playground will be shared the project progresses.

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