Astrid Liverman Former National and State Register Co-ordinator Astrid Liverman is the former National and State Register historian and Preservation Planning unit Director for History Colorado. Astrid Liverman Written by Astrid Liverman National Great Outdoors Month Jun 20, 2017 What better way to celebrate National Great Outdoors Month than to explore some of Rocky Mountain National Park’s National Register-listed trails? Many of the Park’s buildings, resources, and trails are historic. Pagination First page Previous page Page 1 Page 2 Page 3 Current page 4