Simplify the following text for a Grade 5 native English-speaking person.
Original: For the Vietnam War era air base , see Ä Ã Ná ng Air Base or Ä Ã Ná ng International Airport . Da Nang ( occasionally Danang ; in Vietnamese : Ä Ã Ná ng ) is a major port city in the South Central Coast of Vietnam , on the coast of the South China Sea at the mouth of the Han River .
Simplified: Da Nang ( Vietnamese : Ä Ã Ná ng ) is a city in central Vietnam .