Arco
🏙️2 attractions

Arco

Arco, Idaho

The Atomic City

About this city

Also known as: The Atomic City

Arco is a historic high-desert city and the county seat of Butte County, Idaho, beautifully positioned along the Big Lost River at the intersection of three major scenic highways. Originally established as a pioneer junction town known as Root Hog, it entered the global history books on July 17, 1955, by becoming the first community in the world entirely powered by nuclear energy generated at the nearby EBR-I reactor. Nestled beneath the steep jagged peaks of the Lost River Range, it serves as the ultimate modern basecamp for exploring the volcanic wilderness.

Location & Administrative

County
Butte
Time Zone
MST
State Code
ID

Transportation & Accessibility

Nearest Airports
IDAPIHBOI
Getting Around
Car Required

Weather & Timing

Best Months
MayJunJulAugSep
Average Temperature
Peak Season
Hiking SeasonScenic Drive Season
Off Season
Deep Freeze SeasonWinter

Economics & Local Vibe

Population
City proper 840
Sales Tax
6%
Key Industries
Nuclear Research SupportAgriculture & RanchingGeotourism

Practical Tourism Metadata

Suggested stay: 1–2 days

Explore the bizarre dynamic lava tubes and volcanic craters at Craters of the Moon National Monument, view the historic decommissioned EBR-I atomic reactor facility, photograph the historic high school graduation years painted on Number Hill, and trout fish the Big Lost River.

Must-See