Opar is also the setting of Philip José Farmer's novels Hadon of Ancient Opar (1974) and Flight to Opar (1976), which focus on the ancient history of the city some 10,000 years in the past.
While Farmer wrote only two finished Opar novels, he originally planned to continue the series, and in fact left two incomplete Opar works, the novel The Song of Kwasin and novella "Kwasin and the Bear God."