Published
The Yellowstone Branch: Island Park's railroad grade
Why a grade runs through the caldera
Long before US-20, the road through here was steel. The Yellowstone Branch was the Union Pacific’s line to Yellowstone’s west gate, and the federal nomination for the railroad’s terminus district records the decision in one sentence: with the park’s popularity rising, Union Pacific officials “decided to put a branch line through to the west side of the Park from Ashton, Idaho.” The nomination dates the work plainly:
“Work on this line commenced in 1905 and was completed by 1907.”
— National Register of Historic Places nomination, West Yellowstone Oregon Shortline Terminus Historic District. Retrieved 5 October 2026
The county’s own historical society fills in the order and the owner: after a 1905 tour through the park, E. H. Harriman of the Union Pacific “ordered the construction of a rail line from St. Anthony, Idaho to the park’s western border in Montana”, to be run by the Oregon Short Line, a Union Pacific subsidiary. “Work on grading and laying rails began late in 1905”, and the finished line ran 70 miles from St. Anthony to the park boundary — crossing the caldera floor that cabin ground occupies today, on the grade you can still walk.
The two dates, honestly
Local histories disagree on the first train, and this page prints the disagreement rather than hiding it. On the completion of the line itself the sources agree: the county historical society records that “The final line was laid next to the western park boundary on November 12, 1907” — the date the trail’s historians call the golden spike. On the first passenger train they split. The county account:
“The first passenger train arrived in West Yellowstone (Riverside) on June 11, 1908.”
— Fremont County Historical Society, “The Yellowstone Branch”. Retrieved 5 October 2026
The Yellowstone Shortline Trail’s history agrees — first passenger train 11 June 1908. But the local book History of Island Park (Dean H. Green), quoting the railroad historian M.D. Beal, names the engineer instead and gives a different season: “George H. Baker was the engineer of the first passenger train to reach West Yellowstone” — with the entry dated June 5, 1909 in that account. The visitation record leans toward 1908: the county society counts 7,172 people through the west gate in 1908, the year it says train service began, against 4,105 the year before. A buyer reading an old grade does not need the tie broken; both dates are printed as their sources hold them.
A seasonal railroad by design
The branch ran on the same calendar a cabin build does. Service was summer-only, and the reason was the snow this site keeps returning to:
“Train service to West Yellowstone was limited to the months of June to September as the lines between Ashton and West Yellowstone were not kept open during the winter due to heavy snowfall.”
— Fremont County Historical Society, “The Yellowstone Branch”. Retrieved 5 October 2026
Beal’s passage, quoted in the History of Island Park account, puts numbers on the enemy:
“The fifty-seven mile stretch of track connecting Ashton, Idaho and West Yellowstone, Montana becomes snowbound annually by depths varying from six to thirty feet.”
— M.D. Beal, quoted in “History of Island Park” (Dean H. Green), via islandparkidaho.com. Retrieved 5 October 2026
Every March, the railroad ran what the county society calls the Spring Campaign — a four-day push, in the Beal account, with a wedge plow for shallow snow and a rotary plow (a spinning fan-blade machine thrown against the drifts by a locomotive) that hurled snow seventy-five feet and cut a corridor fifteen feet wide. The deepest drifts sat at Rea’s Pass, 6,934 feet on the Continental Divide, about ten miles south of the terminal. When a builder here wonders what “seasonal access” really means, the answer is older than the trucks: a railroad that could afford anything still shut this stretch down every winter and spent four days a spring reopening it.
What the railroad did to the map
Two towns exist because of this line, and the county’s shape still follows it. The Green account credits the 1905 project with giving “the impetus for the organization of two, new towns to be laid out as connecting points on the route” — Ashton, Idaho and West Yellowstone, Montana. The federal nomination picks up the Montana end: the town of West Yellowstone “had its beginnings in June of 1908” when the Forest Service platted a townsite against the park boundary, and the Union Pacific built its depot, baggage building, dining hall and dormitories there between 1907 and 1927 — the permanent depot in October 1909, per the trail historians. The branch carried the crowds:
| Year | West-gate entries | Arriving by rail | Source |
|---|---|---|---|
| 1907 | 4,105 | — | Fremont County Historical Society |
| 1908 | 7,172 | train service begins | FCHS |
| 1912 | 10,783 | — | FCHS |
| 1915 | 32,551 | 29,706 | FCHS |
| 1919 | 23,558 | 8,897 (post-war) | FCHS |
In its early years the branch was, by the county society’s measure, “garnering over 50% of all train passengers coming to the park” — the west gate became Yellowstone’s busiest entrance on rails the Union Pacific laid at Harriman’s order. The same money held the ranch country south of the reservoir as a private retreat — the Harriman park page tells that half — and together they explain how a county of lodgepole and meadow acquired its roads, its towns and its visitors in one decade.
The end: December 1978
The branch died the way seasonal railroads did — slowly, then by ledger. The trail historians date the turn: “Following years of declining passenger service, the Union Pacific ends regular passenger service to West Yellowstone after the 1960 tourist season.” Freight and the park’s needs kept the line on paper nearly two more decades; the Green account ends it with two sentences:
“The Union Pacific System Timetable, dated December 10, 1978, was the last time the line was included in their timetable system. In 1979, the abandoned line was sold to a salvage operator who lifted the tracks and ties.”
— “History of Island Park” (Dean H. Green), via islandparkidaho.com. Retrieved 5 October 2026
A salvage operator is a buyer of dead railroads who recovers the steel and ties for scrap; what the account calls the right-of-way — the legal strip the railroad occupied — was, in its words, returned to nature. Seventy years, roughly St. Anthony 1905 to the salvage crews 1979, is the branch’s whole life. This page deliberately prints no cleaner “abandonment granted” date than that: the regulatory docket of the era is not pullable today, and the timetable and the salvage sale are what the sources hold.
The grade as a neighbour
What the railroad left behind is the flattest, straightest, permanently unbuilt corridor in the county — and it passes through cabin country as trail. The Green-sourced account describes the district’s stretch as roughly a 23-mile run, reached at the crossings of Big Springs Loop Road, Chick Creek Road and Eccles Road, used as an ATV, mountain-bike and horse trail in summer and maintained as a snowmobile trail in winter. For a lot beside it, that is the whole disclosure: a neighbour that will never plat, never build, and never change ownership into a subdivision — the same permanence the federal bank across the river gives the Coffee Pot reach, arrived at by abandonment instead of reservation. On the Montana end the old line is being reborn on purpose: the nonprofit Yellowstone Shortline Trail completed its first nine miles in 2023, running toward the historic depot district where the Museum of the Yellowstone now occupies the Union Pacific’s station.
Reading the grade before you buy
- Find the grade on the parcel’s maps and walk it: a rail bed is engineered ground — level, drained, and usually the driest line through wet caldera country, which cuts both ways for the lot beside it.
- Check which side of the corridor the lot sits on and where the nearest trail crossing is; summer traffic is ATVs and bikes, winter is the snowmobile network the groomed-trail page explains — including what living on the network asks of a homesite.
- Ask about the grade’s own water: a century-old bed carries drainage along its whole length, and the wet spots stay put — the spring-melt questions the caldera page raises apply doubled near old rail fill.
- Visit in both seasons, the way the railroad itself had to: August for the trail traffic, March for the drifts — the two months that ran the branch’s calendar still run a build’s.
- Enjoy the neighbour few places get: a corridor that arrives already cleared, already level, already public — and then run the ordinary cabin questions the before-you-build page keeps in order.
The Yellowstone Branch is the county’s first road, its reason for two of its towns, and the shape under a 23-mile trail — a railroad that fought thirty feet of snow every spring for seventy years and left the flattest ground it could not keep.
Common questions
When was the railroad through Island Park built?
The Union Pacific's Yellowstone Branch was built from St. Anthony, Idaho to West Yellowstone, Montana — about 70 miles — with work beginning in late 1905 and the final rail laid at the park boundary on November 12, 1907, per the National Register nomination and the Fremont County Historical Society.
When did the first passenger train reach West Yellowstone?
The county historical society and the Yellowstone Shortline Trail's historians both say June 11, 1908. The local book 'History of Island Park', quoting railroad historian M.D. Beal, dates the first train June 5, 1909 and names its engineer, George H. Baker. The 1908 west-gate entry count (7,172, up from 4,105 the year before) supports 1908 service; the disagreement is printed as the sources hold it.
Why did the Yellowstone Branch only run in summer?
Snow. The 57-mile stretch between Ashton and West Yellowstone became snowbound annually under six to thirty feet of snow, so trains ran June to September only, and each March the railroad ran a four-day Spring Campaign with wedge and rotary plows to reopen the line — the deepest drifts at Rea's Pass, 6,934 feet on the Continental Divide.
When did the Yellowstone Branch close?
Regular passenger service ended after the 1960 tourist season. The line last appeared in the Union Pacific system timetable dated December 10, 1978, and in 1979 the abandoned line was sold to a salvage operator who lifted the tracks and ties — per the account in Dean H. Green's 'History of Island Park'.
Can you ride the old railroad grade today?
Yes. Roughly 23 miles of the old bed run through the Island Park district as a trail — accessed at the Big Springs Loop Road, Chick Creek Road and Eccles Road crossings — used by ATVs, mountain bikes and horses in summer and maintained as a snowmobile trail in winter. On the Montana end, the nonprofit Yellowstone Shortline Trail completed its first nine miles in 2023.
What does an old railroad grade mean for a cabin lot beside it?
A permanently unbuilt, publicly used corridor: it will never plat or build, its summer traffic is trail traffic, its winter use is snowmobile grooming, and its engineered bed carries drainage along its whole length — worth checking which side of those three facts the lot sits on before you offer.