The man found dead in Seven Sisters Country Park at Exceat in the early hours of Friday (September 6) has been formally identified.
He was John Gilbert, 76, of The Waldrons, Croydon.
A 78-year-old woman was arrested and questioned on suspicion of murder and has been released on bail until October 10.
Officers from the Surrey and Sussex Major Crime Team are investigating.
The man and woman are known to each other and police are not looking for anyone else.
Officers are waiting for further test results for an exact cause of death.