Northern Pacific steam locomotive 4016 at Easton, Washington, on September 08, 1943. Number 4016 is a class Z-3 built by Alco-Brooks in 1917. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive in roster photo

Northern Pacific steam locomotive 4015 at Yakima, Washington, on June 27, 1937. Number 4015, a class Z-3 built by Alco-Brooks in 1917, is parked next to the Yakima roundhouse. Photo by Herman Hunt, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roundhouse

Westbound Class Z-3, Northern Pacific 4015, passes the depot at Wymer, Washington, on June 14, 1944. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, freight train.

Northern Pacific steam locomotive 4015 at Martin, Washington, in July 1944. Number 4015 is a class Z-3 built by Alco-Brooks in 1917. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive in roster photo

Northern Pacific 4015 waits at Martin, Washington, for its turn to travel through the Stampede Tunnel number 3 in 1943. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, freight train.

Northern Pacific steam locomotive 4014, circa 1938. Number 4014 is a class Z-3 built by Alco-Schenectady in 1913. Photo by Herman Hunt, J.M. Fredrickson collection. Other Subject Classes: steam locomotive in roster photo

Two class Z-3 helpers, including number 4014, sandwich a wood caboose on the rear of an extra freight west at Easton, Washington, in 1943. This is the normal "one-in, one-on" helper configuration referring to one helper in the train and one on the rear of the train used on Stampede Pass. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, freight train, wood caboose.

Northern Pacific steam locomotive 4013 running light to Auburn at Tacoma, Washington, on March 19, 1936. Number 4013 is a class Z-3 built by Alco-Schenectady in 1913. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive in roster photo

Northern Pacific steam locomotive 4013 fresh out of the shops at South Tacoma, Washington, circa 1936. Number 4013 is a class Z-3 built by Alco-Schenectady in 1913. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive in roster photo

Northern Pacific steam locomotive 4013 cupled to another Z-3 locomotive at Lester, Washington, circa 1915. Number 4013 is a class Z-3 built by Alco-Schenectady in 1913. Photo by L.B. Waters, J.M. Fredrickson collection. Other Subject Classes: steam locomotive in roster photo