Southbound BNSF stack train STACOMA (Tacoma to Omaha) emerges from within the rocky confines of Sheep Canyon north of Greybull, Wyoming, on June 21, 2017.

Rumbling along the rocky cliffs at the bottom of Sheep Canyon on June 21, 2017, is a southbound BNSF stack train headed for a crew change at Greybull, Wyoming.

Dwarfed by the rugged cliffs of Wyoming’s Sheep Canyon, an eastbound BNSF stack train passes milepost 414 on the Casper Subdivision on June 21, 2017.

On a sunny June 21, 2017, a southbound BNSF stack train appears beneath the rocky cliffs of Sheep Canyon north of Greybull, Wyoming.