It was the night of June 22 that the police were alerted to Frykenbaden's campsite in Kil where a 76-year-old woman was found lifeless in a caravan.
Her 77-year-old husband was arrested and detained on suspicion of murder.
According to the indictment, the woman died by strangulation or suffocation.
The suspect denies the crime and states that it was a fight where he acted in self-defense.
The trial is expected to last three days.