Wikipedia page about this book: https://en.wikipedia.org/wiki/A_Lady%27s_Life_in_the_Rocky_Mountains

Release date is 1996-12-01

"A Lady's Life in the Rocky Mountains" by Isabella L. Bird is a travel book published in 1879. Compiled from letters to her sister, it chronicles Bird's 1873 journey through the Colorado Rockies on the American frontier. Guided by the enigmatic desperado Rocky Mountain Jim, Bird becomes the first white woman to summit Longs Peak. Her vivid account of wilderness adventures and frontier life became an instant bestseller, helping establish her pioneering reputation as an explorer. (This is an automatically generated summary.)

Original publication data not identified