From Kos: Nisyros Island Volcano and Panagia Spiliani

Depart from the port of Kardamena in Kos and take a 1-hour cruise to the volcanic island of Nisyros. Upon arrival, transfer to a waiting bus that'll take you on a short drive to the volcano. Listen to an informative guide along the way.
Get information about the volcano and the history of the island. Then, feel the force of the lava rumbling deep beneath your feet as you enter the volcanic crater. See the bubbling mud pools and steam geysers, and imagine that you have landed on the moon.
Return to the port and get the chance to wander around the town of Mandraki. After a short walk through the narrow streets of blue and white painted houses, visit the monastery of Panagia Spiliani, considered one of the most beautiful monasteries of the Greek Islands.
Make your way back to town for some free time for lunch (own expense) or do some shopping before boarding the boat back to Kos at 4:00 PM.