The Temple of Apollo in Pamukkale, Turkey is a historical site that dates back to ancient times. It was built on a cave that emanated carbon dioxide, giving it the nickname "Plutonion." The temple was once the heart of the city, where people would come to consult the oracle and give sacrifices to the gods at the adjoining spring, known as the Plutonium. The spring was known to emit toxic fumes that could kill small animals and birds, and only the temple's eunuch priests were said to understand the secret of holding their breath around the fumes.

The temple is relatively well-preserved and has large steps leading to a platform that is 2.5 meters high. A peribolos, an enclosed area, is located in front of the temple and measures approximately 20 meters by 15 meters. It is believed to have been built in the 2nd century and is considered one of the largest temples in the world. It was also included in the UNESCO World Heritage List. Visitors can explore the ancient ruins and admire the historical significance of the Temple of Apollo in Pamukkale, Turkey.