BNSF 2745 (GP39E) runs through the yard in downtown Denver, Colorado.

Union Pacific's Big Boy #4014 (4-8-8-4) backs into the UP's North Yard in Denver, Colorado where it will stay for two days before heading back to Cheyenne, Wyoming.

Union Pacific's Big Boy #4014 (4-8-8-4) crosses Sand Creek as it heads west on the Belt Line towards the UP's North Yard in Denver, Colorado.

BNSF 8412 (SD70ACe) leads a freight out of the yard in Denver, Colorado.

BNSF 8998 (SD70ACe) leads a train out of the yard in downtown Denver, Colorado.

BNSF 6618 (ES44C4) leaves the Denver Yard with a train bound for the Joint Line.

A rail inspection truck passes a pair of heavies waiting in the Denver Yard.

UP 7891 (ES44C4) heads into the Union Pacific's North Yard in Denver, Colorado.

A grain train leaves the Denver Yard, passing a pair of engines waiting on the ready track for a train assignment.

UP 5586 (AC4400CW-CTE) moves through the North Yard in Denver as heads to the fuel and sand servicing island.

BNSF 8753 (SD70ACe) and mate moves into the Denver yard to a waiting train.

BNSF 1958 (SD40-2) runs under a signal tower in the North Yard in Denver, Colorado.

BNSF 1448 (SD60M) is a former Burlington Northern motor built in 1991, and now sports a Heritage III paint scheme.

NS 4130 (AC44C6M) passes markers in the oldest cemetery in Denver, the Riverside Cemetery.

BNSF 1600 (SD40-2) works the yard in Denver, Colorado, sorting cars into the various ladders.