Strangers in a strange land. Eagle eyed railfans will notice a pair of visitors waiting for service in the Union Pacific's North Yard in Denver, Colorado.

UP 845 (GP38-2) works sorting freight cars in the Union Pacific's North Yard in Denver, Colorado.

UP 845 (ex MKT GP38-2) works the Union Pacific's North Yard in Denver, Colorado, while a couple of BNSF motors line up for sand and fuel.

UP 845 (GP38-2) works deep in the North Yard in Denver, Colorado.

UP 845 (an ex Missouri Kansas Texas GP38-2) works the Union Pacific's North Yard in Denver, Colorado.

UP 845 (GP38-2) leads a bay window caboose used as a shoving platform through the North Yard.

UP 845 (GP38-2) works an industrial yard in Commerce City, Colorado.

UP 845 (GP38-2) works the Union Pacific's North Yard in Denver, Colorado.

UP 845 (GP38-2) sits in the North Yard along with a Southern Pacific patched unit.

The sun has just risen as UP 845 (GP38-2) works a cut of cars into the ladder in the Union Pacific's North Yard in Denver, Colorado.

UP 845 (GP38-2) has just released a cut of cars into the Union Pacific's North Yard in Denver, Colorado.

UP 845 (GP38-2) is getting covered in thick snow from a winter storm that has blanketed the Colorado Front Range.

Long shadows in the early minutes of sunrise creep across the Union Pacific's North Yard as UP 845 (GP38-2) gets a early start sorting cars.

The flashing light on UP 845 (GP38-2) indicates that the tank is configured for remote operations.

UP 845 (GP38-2) sits with other light and heavy power waiting for service or assignments in the UP's North Yard in Denver, Colorado.