Butte County


Land Area: 2,237 square miles

Established February 6, 1917 with its county seat at Arco. It was named for the buttes that rise from the Snake River plain and served as landmarks to trappers and pioneers who traveled through the area. The first white men in the region were thought to be Donald Mackenzie and his Northwest Fur Company trappers in 1818.

County Clerk

Butte County Administrative Offices

205 West Grand Avenue
Arco, Idaho 83213-0737

Phone: (208) 527-3021
Fax: (208) 527-3295


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  • Driver’s License Renewal
  • Vehicle Registration
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Cities in Butte County

County Seat: Arco

(Incorporated cities shown only.)

About Butte County

Find Butte County Idaho on a map



Arco is a city in Butte County, Idaho, United States. The population was 995 at the 2010 census.[4] Arco is the county seat and largest city in Butte County.[5]


Originally known as Root Hog, the original town site was five miles (8 km) south at the junction of two stagecoach lines (Blackfoot-Wood River and Blackfoot-Salmon). A suspension bridge that crossed the Big Lost River funnelled traffic through the settlement. The town leaders applied to the U.S. Post Office for the town name of “Junction.”

The Postmaster General thought the name too common and suggested that the place be named Arco for Georg von Arco (1869–1940) of Germany who was visiting Washington, D.C. at the time. Georg von Arco was an inventor and a pioneer in the field of radio transmission and would become the lead engineer of Telefunken, a German company founded in 1903 that produced radio vacuum tubes. The town later moved four miles southeast when the stage station was moved to Webb Springs at Big Southern Butte. When the Oregon Short Line railroad arrived from Blackfoot in 1901 the stage lines became obsolete and the town of Arco moved northwest to its present site.[6]

Arco was the first community in the world ever to be lit by electricity generated solely by nuclear power. This occurred for about an hour on July 17, 1955, powered by Argonne National Laboratory‘s BORAX-III reactor at the nearby National Reactor Testing Station (NRTS), which eventually became the site of the Idaho National Energy Laboratory, a predecessor of the current Idaho National Laboratory.[7]


The town’s economic base is primarily derived from the Idaho National Laboratory (formerly the Idaho National Engineering Laboratory or INEL), agricultural products, and recreation in the Lost River Valley.


Arco is located at 43°38′5″N 113°18′5″W (43.634632, -113.301323).[8] The elevation is 5325 feet (1623 m) above sea level.

According to the United States Census Bureau, the city has a total area of 1.07 square miles (2.77 km2), of which, 1.06 square miles (2.75 km2) is land and 0.01 square miles (0.03 km2) is water.[1]

In town, the most striking physical feature is Number Hill, a rocky hill with numbers painted all over it. Butte County High School has a tradition of each class since 1920 painting its graduation year on the face of hill.[9]


City of Moore

Moore is a city in Butte County, Idaho, United States. The population was 189 at the 2010 census.


Moore is located at 43°44′8″N 113°22′1″W (43.735517, -113.366952).

According to the United States Census Bureau, the city has a total area of 0.29 square miles (0.75 km2), all of it land.


Custer County

Historical and scenic Custer County, founded in 1881 and located in Central Idaho, has a population of 4,368 and an area of 4,938 sq. miles. It’s landscape consists of arid desert, flat green valleys, and rugged rocky peaks and contains the highest mountain in Idaho, Mount Borah at 12,662 ft.

The County seat is Challis, with a population of just over Idaho map with Custer County highlighted1,000. Other towns include Mackay, Stanley, and Clayton. Custer County relies on ranching, mining, and tourism as its main resources.

Custer County contains much of the Frank Church River of No Return Wilderness and the famous Salmon River as well as the Sawtooth National Recreation Area.

Custer County info

City of Mackay

City of Mackay
203 South Main Street
P.O. Box 509
Mackay, Idaho 83251

Phone: 208-588-2274
FAX: 208-588-2274

The City of Mackay (pronounced MACKee) was founded in 1901 by Wayne Darlington, the head mining engineer for John W. Mackay of Nevada Comstock Load fame. Mackay was the money behind the mines located below Mackay Peak near the now ghost town of White Knob at that time. Although named after him, Mackay never set foot in the town. The town of Mackay was located at the end of the Oregon Short Line Railroad which was brought across the desert from Blackfoot to ship supplies into the mines and products from the mines. Buildings from the once thriving town of Houston were moved 5 miles to the rails end resulting in the death of Houston and the birth of Mackay.

Mackay has a rich mining and associated logging history as well as farming and ranching. With mining and logging essentially shut down, the main economy now revolves around farming and ranching, tourism, and the Idaho National Laboratory.
City of Mackay info