Glacial Erratic / Day 31 / Letcher, South Dakota / Mile 1,400. Photo by Chris Register/www.conversationswithus.com

Glacial Erratic / Day 31 / Letcher, South Dakota / Mile 1,400. Photo by Chris Register/www.conversationswithus.com
Glacial Erratic / Day 31 / Letcher, South Dakota / Mile 1,400. Photo by Chris Register/www.conversationswithus.com