ICAO		IATA		Other		Location
KEFC				EFC		Belle Fourche [Muni], South Dakota, US (170 mi / 274 km E)
				3MT3		Ryegate [Three Cross Ranch Airport], Montana, US (171 mi / 274 km NW)
				3SD5		Lead [Dilligaf Heliport], South Dakota, US (171 mi / 275 km E)
				SD90		Spearfish [Mitchells Strip], South Dakota, US (171 mi / 275 km E)
KRPX		RPX		RPX		Roundup, Montana, US (171 mi / 276 km N)
KSPF		SPF		SPF		Spearfish [Black Hills-Clyde Ice Field], South Dakota, US (171 mi / 276 km E)
				JECA		Jewel Cave National Monument [Jewel Cave NM], South Dakota, US (172 mi / 276 km E)
				MT29		Miles City [Sunday Creek Airpark], Montana, US (172 mi / 277 km N)
KLSK		LSK		LSK		Lusk [Muni], Wyoming, US (172 mi / 277 km SE)
				WY25		Wheatland [Snell - North Laramie River Airport], Wyoming, US (173 mi / 278 km SE)
				GRTE		Grand Teton National Park [Grand Teton NP], Wyoming, US (175 mi / 282 km W)
				6S0		Big Timber [Big Timber at Howard Field], Montana, US (176 mi / 283 km NW)
				97M		Ekalaka, Montana, US (176 mi / 283 km NE)
				MT45		Ekalaka [Castleberry Airport], Montana, US (176 mi / 283 km NE)
				8U0		Ryegate, Montana, US (176 mi / 284 km NW)
				6V0		Edgemont [Muni], South Dakota, US (180 mi / 289 km E)
				6SD4		Edgemont [Xpoint Airport], South Dakota, US (180 mi / 289 km E)
KJAC		JAC		JAC		Jackson [Jackson Hole Airport], Wyoming, US (180 mi / 290 km W)
				0SD9		Custer [Crazy Horse Heliport], South Dakota, US (180 mi / 290 km E)
				0SD5		Custer [The Fort Heliport], South Dakota, US (180 mi / 290 km E)