Paya Nakhon Cave, Hua Hin, Thailand, this is a magical tiankeng hidden in the mountains. Later, the Five Emperor of Thailand built a pavilion in the cave to worship the gods. It took more than three hours to walk by boat and walk. Going into the cave, climbing the mountain is super tired! Every day, between 12 and 3 noon, the sun will shine on the pavilion, so its a good time to go.