Cappadocia is an upside-down world: its cities are subterranean, while its overground landscape is like the interior of a cave system, covered in stalagmite-like rock pillars known as fairy chimneys.

Now they’re one of Turkey’s most striking tourist attractions, often viewed from the air by the floating legions of hot air balloons that regularly fill the sky.

Set in central Turkey’s otherworldly Cappadocia region, this year’s iteration of the Echoes From Agartha festival continued to tell its elusive story. The festival is based on the mythical ...