Coconino County, Arizona: Area = 18,661 sq mi (48,332 km²)

Coconino County in northern Arizona is the second-largest county by area in the contiguous United States (after San Bernardino County, CA).

• Total area: 18,661 sq mi (48,332 km²)
• Land area: 18,619 sq mi (48,224 km²)
• Water area: 42 sq mi (108 km²) — includes Lake Powell (Glen Canyon), Lake Mead fringe, Mormon Lake, numerous reservoirs.

Geographic Diversity

The county spans 5,000+ ft (1,500 m) of elevation relief:

• Colorado Plateau – Vermilion Cliffs, Paria Canyon, Marble Canyon.
• Grand Canyon – Entire north rim + most of south rim within county.
• San Francisco Peaks – Humphreys Peak (12,633 ft / 3,851 m), Arizona's highest point.
• Mogollon Rim – Escarpment marking plateau edge; ponderosa pine forest (largest contiguous stand in US).
• Painted Desert / Petrified Forest (NE corner).

County seat: Flagstaff (pop. ~76,000). Other communities: Page, Williams, Sedona (part), Tuba City, Fredonia.