Three Feet Between the Rails

The three-foot-gauge track of the Durango & Silverton Narrow Gauge Railroad runs along the Animas River, its two steel rails set thirty-six inches apart. Standing on the ballast, the space between the rails reads not as a weakened railroad but as a different kind of machine, too narrow for comfort, too precise for error.

That measurement is the line's whole engineering argument. Standard gauge is fifty-six and a half inches; this one is twenty inches narrower. The savings came in every cut, every fill, every bridge: less earth to move, less iron to roll, less weight in ties and ballast. But the cost was permanence, a three-foot-gauge road cannot serve a mainline. It belongs to the country it was laid through. A narrow line can bend around a cliff without a trestle, and it can climb a grade that would make a standard engine dig its drivers in. Nineteenth-century builders chose three feet for branch lines and mountain crossings where every mile of earthwork was money, and the Durango run kept that width for the same reason.

The rails are short lengths of steel, jointed with fishplates and bolts that a section hand can draw up with a track wrench. There is a rhythmic knock at every joint when a train rolls: the wheels dropping the half-inch transition, the rail flexing on its seat. The spikes are long and flat-headed, driven at a slight angle into the tie so that the head hooks over the rail's base. A loose spike sings when the train passes. The section crew listens for that sound, and a turn of the wrench or one new spike stops it.

The ties are oak, spaced close, many still in place after years under load, others newly squared. The ballast is broken stone of the local mountains, gray and purple, sharp edge to sharp edge. A few spots have sunk, and a section crew levels them with shovel and beat-board. In the high cuts, snow remains through the first weeks of summer, filling the gauge with white, then contracting to a wet shadow between the ties. In autumn, leaves polish the rail heads slick, and the first hard frost heaves a tie out of the bed; the crew taps it back down by sight.

The track is not a preserved exhibit. It has been in service since the first trains climbed to Silverton in the 1880s. The mine traffic is gone, but the excursion trains are heavy, and the track carries every one on the same alignment, some of it original. The crew walks the line once a day, checking for sun kinks. At speed, the train rocks. The flanges grind the inside of the rail on every curve, working the steel into a bright, silvery face that never rusts. The top of each rail is a ribbon of polish. The gauge itself, the thirty-six inches between the heads, holds steady through the bends. A welded steel device checks it: two fingers set exactly the same distance, fitted across each rail pair. On the south-facing side of the canyon, the afternoon sun warms the rail enough to push at the joints, and the section crew walks there late to open the bolts. Under the weight of a passing train, the rail head moves a visible fraction of an inch, a flex the afternoon light catches at every joint.

The outside rail of the curved track leans into the turn, its inner face worn bright where the flanges ride.

Durango & Silverton Narrow Gauge Railroad