Our day trip to the Nisyros volcano and the island's largest town of Mandraki was the highlight of our holiday to Kos. I had been to volcanic areas in Iceland and Kenya before, but I had never walked in an actual crater, which was an impressive experience. Walking in the sulphur smells, between steam vents in the ground and holes at the bottom of which you can actually see bubbling, boiling, smelly water is amazing. And the views while driving in the hills forming the edge of the crater are divine. The town of Mandraki itself is the cutest little island capital, with picturesque houses and lovely cafes overlooking the sea. Walking up the steps to the monastery is well worth the trouble, and buying some of the local almond drink provides for a perfect, sweet end of the day.