When Jim Shaughnessy began photographing the American railways, the transportation infrastructure was in a major time of change. In the 1950s and ’60s, diesel trains were replacing the steam locomotives whose chimney exhaust had rose above the steady expansion of the lines. As the 20th century went on, local tracks were abandoned, highways consumed much of the freight traffic, and former railroad passengers took to airplanes or their own cars for travel.

Shaughnessy, now in his 80s, has an archive of around 60,000 images that chronicle these decades of railroad activity. Jim Shaughnessy Essential Witness: Sixty Years of Railroad Photography, out now from Thames & Hudson, features a survey of 150 images. The black and white photographs concentrate on the era of midcentury flux, and the cultural environment of the railroad. Trudging through snow to get the right angle on a locomotive as it barreled over a winter landscape in Quebec, or framing a quiet scene where a cat rubbed against the leg of a night watchman in Hardeeville, South Carolina, Shaughnessy sought to capture every aspect of the railroad.

“Always restless, even daring when he had to be, Shaughnessy worked hard to get in and around the railroad, in all conditions, in all settings,” writes Kevin P. Keefe, former editor-in-chief of Trains magazine, in a book essay. “If the life of a crossing watchman was important, then Shaughnessy shuddered through a subzero night until the perfect moment when his subject dashed back into the warmth of a shanty. If the guts of a steam locomotive were interesting, then he’d insert himself into the depths of roundhouses and sidle up next to the hostlers in order to record the oily intricacies of valve gear and side rods.”

Born in Troy, New York, in 1933, Shaughnessy published his first photograph in Trains in 1952. While the detailed captions in Essential Witness are those of a true rail enthusiast (the “Pennsylvania Railroad 11-class 2-10-0” is identified as chugging over an elevated bridge), his images have a broader appreciation for how people exist with the railroads in North America, and how these systems altered the landscape. The silhouette of a tunnel in Canaan, New York, in 1989 reveals its jagged edges, framing the train with this rock that was blasted through for progress. Sometimes the trains are tiny against the mountains or waterfalls, sometimes the focus is elsewhere, like a 1953 photograph that concentrates on the cows in a Vermont pasture, unperturbed by the freight train zooming behind.

Some of the most compelling images are at night, when Shaughnessy uses available light rather than flashbulbs or other artificial illumination. A GG1 electric locomotive, its curves given streamlined style by industrial designer Raymond Loewy, appears spectral with its headlights shining through an Ivy City, Maryland, service facility. In a 1961 photograph, a yardmaster on the back of a caboose in Mechanicville, New York, is spotlit by his lantern. Essential Witness is notably free of any train calamity or collision. Instead, it uses Shaughnessy’s lifetime of railroad photography to visualize these moments of industry, and the people behind them.

Jim Shaughnessy Essential Witness: Sixty Years of Railroad Photography is out now from Thames & Hudson.