What best describes writing that is the retelling of an event personally witnessed by writer?

The best description for writing that is the retelling of an event personally witnessed by the writer is "personal narrative." Personal narratives are written accounts of events, experiences, or stories that are based on the author's own personal observations and involvement. These narratives often provide firsthand perspectives and insights into the events being recounted, as the writer draws upon their own memories and experiences to narrate the story.