Floating on my back in the azure blue of Sawajiri Bay, I found myself falling under the spell of this tiny volcanic island — a little piece of paradise that bubbled up from the depths of the Pacific Ocean many millennia ago.

Swirls of dark volcanic rock rearing up out of the sea bear silent witness to Kozushima's violent past. But trek higher up the rocky slopes and you'll find them covered in a blanket of thick forest that lends an almost benign appearance to Mount Tenjo as its table-top 572-meter peak towers over this 19-sq.km speck of land that is administratively part of Tokyo — though separate and apart in just about every other imaginable way.

A mere 35 minutes from the capital by plane, Kozushima — which is home to fewer than 2,000 residents — is less touristy than its neighbors in the Izu Islands chain. For the visitor, that translates into it offering a particularly peaceful experience, albeit one without many of the usual amenities — most notably, the absence of any stores or eateries within easy reach of the campsite.