A stunning meditation on the ancient trees living among us and an urgent call to protect them. Some trees have stood for thousands of years, surviving empires, urban expansion, ecological collapse, and dramatic shifts in climate. Living among us--often unnoticed--they are the elders of our multispecies communities, sustaining complex ecosystems while bearing witness to generations of human history. The Oldest Tree is a global archive and love letter to these extraordinary beings. Bringing together artists, writers, scientists, and researchers from Greece to Japan to Mexico, Lily Consuelo Saporta Tagiuri creates a powerful conversation around stewardship, ecological memory, and survival. Blending art, science, and environmental storytelling, this book documents some of the world's oldest trees not simply as natural wonders but as living records of resilience and interdependence. At a moment of accelerating climate crisis, The Oldest Tree asks what it means to truly notice the life around us and what responsibility comes with that recognition.