Kneeland Airport (IATA: NLN, FAA LID: O19) is a public airport operated by Humboldt County 10 miles (16 km) southeast of Eureka, California. Located on a mountain ridge at over 2,700 feet (820 m) above sea level, this airfield is used by general aviation aircraft, which sometimes seek an alternate airport when nearby low-lying airports are under fog. The airport has a California Dept. of Forestry (CDF) Helitack Station. Kneeland Airport is also used as an excellent sky watching location for the Humboldt Astronomers club.