When Julia Martin visits the Greek islands of the Dodecanese, beauty and suffering seem inextricable. On the Sponge Islands follows her journey through Rhodes, Symi, Halki, Kalymnos, and Patmos to trace the cultural and ecological legacy of sponge diving. Because of their wonderful porosity, sea sponges have always been perfect for a myriad of human uses, and men from the islands had been diving for them and trading them since antiquity. In the late nineteenth century new deep sea diving suits made it possible to mine the seabed as never before and bring home untold wealth. It was a rich harvest that came at the cost of many lives. And it couldn't last. Everything, one might say, flowed through sponges. Until it didn't. Over three visits, Martin meets Aphrodite, Lefteris, Manuel, Zinovia, and others whose lives are bound to the sea. Through their stories, she uncovers the rise and fall of the sponge trade and its deep entanglement with environmental devastation. The islands bear the scars of war, both human and ecological. And yet, despite all of this, the Aegean remains a glory of blue. For all of its plunder, the sea is still luminous and alive, and conversations with the islanders keep returning to the heart. On the Sponge Islands brings together natural history, personal recovery, and ecosocial reckoning. Martin's lyrical, searching prose is rich in dialogue, extraordinary characters, and curious tales. While the devastation of the Aegean seabed may mirror the wider ecological catastrophe, the green renewal taking root on some of the islands is an embodiment of hope. This is a story of extinction and resilience, of loss and restoration. It reminds us that it may not be too late--not yet.