Connor Hayes, 25, and girlfriend Joanna Lam, 24 died when a landslide pushed their rented vehicle off Haast Pass road into a swollen Haast River on September 10, last year.
Ms Lam's body later washed up on a West Coast beach, but Mr Hayes' was never found.
Wreckage from the campervan was recovered from the river during a massive search operation.
The inquest, before Coroner David Crerar, is being heard at Greymouth District Court this afternoon.
- Kurt Bayer of APNZ