This year marks the 25th anniversary of a unique exchange between Minnesota and Norway. Troops from Minnesota's National Guard and the Norwegian Home Guard switch places two weeks out of the year and train in each other's country. Minnesotans test their mettle in the snowy mountains and Norwegians tackle the cold Midwest winter. Minnesota Public Radio's Gretchen Lehmann met with some of the Norwegian troops last week at Camp Ripley and has this report.