Book excerpt: Researchers have studied various aspects of the ancient civilization of Sri Lanka and probed deeply into the subject of village tank clusters (tank cascade systems) during the last 4 decades. A wealth of information was gathered and the knowledge of many components has been updated. This book brings you this updated information. The author brings new definitions of tank cascade systems and cascade ecology. The book begins with the historical perspective and moves on to explain various aspects, step by step, such as geography, geology and geomorphology, soil and climate, surface and groundwater, traditional agriculture and water management, flora and fauna, recent studies and the restoration of cascade ecology. The book will interest geomorphologists, geologists, geographers, archaeologists, ecologists, and historians. Specifically, university lecturers, students and researchers will find interest in these pages and may utilize the content to prepare their study materials.