Richard Symonds, of The Ifield Society, discovered what is believed to be an Early Bronze Age Bell barrow, which dates back more than 3,500 years old.
The site is located just below The Druid's Copse near the Scheduled Ancient Monument of Ifield Court Moat in St Margaret's Parish Fields.
This specific area West of Ifield is rich in Neolithic, Celtic, Roman and Anglo Saxon artefacts.
Mr Symonds said: “An Archaeological dig is now critical. Archaeological confirmation by experts is being sought.”
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