Buying Land in Musselshell County, Montana

From cattle roundups to a coal boom -- and back to coal today

Roundup's name comes from its 19th-century role as a natural gathering point for cattle roundups, and ranching -- cattle and, historically, sheep -- has never stopped being central to Musselshell County's economy. But coal, discovered in the Bull Mountains area in 1907 and boosted by the arrival of the Milwaukee Road railroad, briefly reshaped the county into a mining hub: at points there were as many as 26 active mines, with production only slowing when the railroad shifted to diesel and the Depression hit, and the last of the old-era mines had closed by 1959. That history matters for land buyers mainly as context -- much of the county's older private-land pattern and its rail and townsite layout trace back to that coal-and-cattle era, not a purely agricultural one.

Coal came back. Signal Peak Mine, an underground longwall operation in the Bull Mountains straddling the Musselshell/Yellowstone county line, is Montana's only underground coal mine and one of the largest in the country, employing roughly 250-300 workers. In June 2025, the U.S. Department of the Interior approved a mining plan modification authorizing Signal Peak to recover approximately 22.8 million tons of federal coal and 34.5 million tons of adjacent non-federal coal, extending the mine's operating life by up to nine years and, per the agency, expected to generate over $1 billion in combined local, state, and county economic activity. Whatever else it is, this is a live industry actively shaping the county's economy and workforce today, not a 20th-century footnote.

Subsidence litigation: a real issue for land near the Bull Mountains

Signal Peak's mining method -- longwall mining, which lets the mine roof deliberately collapse behind the advancing machinery -- causes measurable subsidence and cracking of the surface above the mined-out area. Multiple environmental and landowner-advocacy groups (including Earthjustice, the Montana Environmental Information Center, and others) have filed litigation, including a lawsuit reported in early 2026, alleging that this subsidence has fractured aquifers and dried up springs and stock wells that area ranchers rely on for livestock water, in a landscape that local reporting describes as already dependent on a delicate network of underground springs. This is squarely relevant to anyone considering ranch, grazing, or recreational land in or near the Bull Mountains: ask specifically about the parcel's proximity to permitted or active longwall mining panels, any documented well or spring impacts on the property or its neighbors, and whether water rights tied to the land have been affected.

A growth policy in progress -- and a zoning question still open

As of the most recent public records available, Musselshell County does not appear to have adopted county-wide zoning at the unincorporated-county level; the City of Roundup has its own separate municipal zoning that applies only within city limits. County commissioners were already discussing the idea of zoning and a development-permit process for the county as early as March 2021, per their own meeting minutes, but no subsequent adoption was found in available public sources -- so treat this as an open question to confirm directly with the county rather than an assumption either way.

What is confirmed is that the underlying planning document is actively being rewritten: in February 2025, commissioners voted to hire WWC Engineering, using a CDBG grant, to update the county's Capital Improvement Plan and Growth Policy, citing the firm's history with the county's earlier plans. Since a growth policy is the legal basis Montana counties use to justify subsequent zoning and subdivision-regulation changes, a buyer with a longer time horizon here should ask the Planning Board directly how that update is progressing and whether zoning or new development-permit requirements are part of the discussion -- the rules that apply to a parcel today are not necessarily the rules that will apply in five years.