Between extremes of climate farther north and south, the 38th North parallel line marks a temperate, middle latitude where human societies have thrived since the beginning of civilization. It divides North and South Korea, passes through Athens and San Francisco, and bisects Mono Lake in the eastern Sierra Nevada, where authors David and Janet Carle make their home. Former park rangers, the authors set out on an around-the-world journey in search of water-related environmental and cultural intersections along the 38th parallel. This book is a chronicle of their adventures as they meet people confronting challenges in water supply, pollution, wetlands loss, and habitat protection. At the heart of the narrative are the riveting stories of the passionate individuals—scientists, educators, and local activists—who are struggling to preserve some of the world's most amazing, yet threatened, landscapes.

Traveling largely outside of cities, away from well-beaten tourist tracks, the authors cross Japan, Korea, China, Turkmenistan, Turkey, Greece, Sicily, Spain, Portugal, the Azores Islands, and the United States—from Chesapeake Bay to San Francisco Bay. The stories they gather provide stark contrasts as well as reaffirming similarities across diverse cultures. Generously illustrated with maps and photos, Traveling the 38th Parallel documents devastating environmental losses but also inspiring gains made through the efforts of dedicated individuals working against the odds to protect these fragile places.