The park is the 1900 square mile Grand Canyon National Park and the walk was an 800 mile slog, below the rim and rarely along the Colorado River, made by two experienced, but hopelessly unprepared hikers. It’s an exhausting but exhilarating read—you will learn about the geology, the archeology, the wildlife, the hydrology, and the local Native Americans of this national treasure, and the politics involved in keeping it from becoming (more) spoiled. If you fear rappelling into a several hundred foot deep slot canyon, then this trip should just remain an armchair exploration.
