Photograph of a man driving a crawler tractor on a railroad track. The machine is an International TracTracTor. Photograph taken from behind the machine as it attempts to turn on the tracks.

Photograph of a group of railroad construction workers standing on railroad tracks in front of a machine mounted on a flatcar. They are laying new railroad tracks. The flatcar is long and carries a locomotive and stacks of wooden planks for construction. Scattered men on the flatcar look at the camera. This construction was part of the extension of the Oregon Electric Railway to Albany and Corvallis. Handwritten note on the back of the print reads, "Oregon Electric track laying machine at work on Albany-Corvallis extension."

Photograph of 4 railroad construction workers standing next to a railroad trestle under construction. The trestle is built across a large field behind the workers and extends into the distance. This construction was part of the extension of the Oregon Electric Railway to Eugene, Oregon. Handwritten note on the back of the print reads, "Temporary trestle to be filled in by Steam Shovel No. 4, Eugene extension of O.E.Ry."

Photograph of 2 groups of men facing each other at a railroad construction site on the Washington side of the Columbia River Gorge. The men on the left stand around a railroad track under construction and watch as a construction worker clears the land. The men on the right appear to be construction workers, and they look up at the other group. Homesteads are visible in the background. Handwritten note on the back of the print reads, "Troubles between the P. & S. and C. Valley men at Carson, Wash." Second note reads, "Near Monaghan Homestead. Return to Traffic Dept., SP.S Ry."

Photograph of railroad construction workers standing in an unfinished rock cut. Steep rock cliffs rise all around them and one person stands on the cliff above them. Railroad tracks, still under construction, end at the rock face behind the workers. Taken on the Washington side of the Columbia River Gorge. Handwritten note on the back of the print reads, "Rock cut at 1488." Second note reads, "MP 52.5 near Carson, tracks at left to river's landing."

Photograph of 4 railroad construction workers standing in an unfinished rock cut. Steep rock cliffs rise all around them. Railroad tracks, still under construction, end at the rock face behind them. Taken on the Washington side of the Columbia River Gorge. Handwritten note on the back of the print reads, "Rock cut at 1488 near Carson landing." Second note reads, "Return to Traffic Dept., SP.S Ry."

Photograph of a crew of 6 men preparing to blast an area for railroad construction for the Portland & Seattle Railway. Likely taken on the Washington side of the Columbia River Gorge. Handwritten label at the bottom of the print reads, "Preparing to Load 30 Ton Blast, P.&S. Ry."

Photograph of a group of railroad construction workers working on a railroad track. They stand between the track and a pile of rocks and dirt. Several carry shovels. Most of them look at the camera. There is a train on the right. Stamp on the back of the print for Arthur M. Prentiss, Commercial Photographer.

Photograph of 4 railroad construction workers working in a trench at the base of a graded hillside in Carson, Washington. They work next to a track that transports construction materials. To the right is the Columbia River and a view of a large mountain on the Washington side of the gorge. Handwriting on the bottom of the print reads, "1516, Finishing Station 1515, June 23 '06, P.&S. Ry." Handwriting on the back reads, "Carson Landing."

Photograph showing construction workers holding picks on a steep hillside near Carson, Washington. Rocks and dirt fall to the ground beneath them. Handwritten note on the back of the print reads, "Trapping at Carson Landing, 1906."

Photographic postcard showing 3 men on an American railroad ditcher belonging to SP&S Railway. The ditcher is on a flat railway car as it moves dirt from the train onto the side of the railroad track. Likely taken in Oregon or Washington. Handwritten note on the back of the postcard reads, "McRyan(?) Collection."

Construction of Spokane, Portland & Seattle Railway Tunnel 15 near Farrington, Washington. Two unidentified people stand on partially constructed railroad tracks underneath a wooden support structure. The Snake River is visible on the left side of the photograph. A handwritten note on the back of the photograph reads, "Cable Dump (?) and Tunnel. Pine Tree Rapids. This fill is 200 feet from bottom coulee to grade. Tunnel 15 west of Farrington, M. P. 266.3"

Two unidentified railroad employees working on a section of track. They are wearing overalls and striped engineer caps. Each person is operating a pneumatic tie-tamper.