Odesa in Ukraine has been added to the cultural sites that UNESCO is highlighting. Also being included are ancient sites in Lebanon and Yemen.
Australian scientists confirm the mass bleaching, yet are hopeful the world's largest coral reef ecosystem can recover.
The damaged sites include churches, historic buildings, museums and monuments. A UNESCO spokesperson said they fear more sites will be added to the list, as the group works to verify the destruction.
Supporters say the tunnel will reduce noise and hide cars for visitors to the prehistoric landmark. Opponents warn of possible damage to the site which archaeologists continue to study.