Isabella Bird's "A Lady’s Life in the Rocky Mountains" documents her travels through the Rocky Mountains in 1873. The book is composed of letters written by Bird to her sister during her journey. She provides vivid descriptions of the landscapes, wildlife, and the rugged conditions of the frontier areas of Colorado. Bird also recounts her encounters with various people, including miners and pioneers, and details her experiences with the unique challenges posed by the harsh and often unpredictable mountain environment. Her narrative captures the isolation and beauty of the Rocky Mountains, as well as the spirit of adventure that characterized her travels.