Question: Which airport is located in North Dakota, Grand Forks International Airport or Knox County Regional Airport?
Context: Emerado is a city in Grand Forks County, North Dakota, United States located near Grand Forks Air Force Base.  It is part of the "Grand Forks, ND-MN Metropolitan Statistical Area" or "Greater Grand Forks".  The population was 414 at the 2010 census.  Grand Forks Air Force Base is located near Emerado. The John D. Odegard School of Aerospace Sciences (UND Aerospace) is a multidisciplinary college within the University of North Dakota (UND) in Grand Forks, North Dakota.  The school was formed in 1968.  The majority of the school's fleet of over 120 aircraft is based at nearby Grand Forks International Airport and is the largest fleet of civilian flight training aircraft in North America.  UND Aerospace also operates flight training centers in Crookston, Minnesota, and Phoenix, Arizona.  Today, the school has many aerospace-related programs including commercial aviation (fixed wing and rotorcraft), air traffic control, airport management, Space Studies, Computer Science, Atmospheric Sciences, and Earth System Science & Policy.  Currently, the school has over 500 faculty and 1,900 students making it the second largest of UND’s degree-granting colleges.  The present dean of the school is Dr. Paul Lindseth. Downtown Grand Forks is the original commercial center of Grand Forks, North Dakota.  Located on the western bank of the Red River of the North, the downtown neighborhood is situated near the fork of the Red River and the Red Lake River.  While downtown is no longer the dominant commercial area of the Greater Grand Forks community, it remains the historic center of Grand Forks.  An 80.4 acre portion was listed on the National Register of Historic Places in 2005, as Downtown Grand Forks Historic District.  Today, downtown Grand Forks is home to many offices, stores, restaurants, and bars. Grand Forks Municipal Airport is a former airport, located within current city limits approximately 3 mi west-northwest of central Grand Forks, North Dakota.  It was closed shortly after World War II and is now redeveloped as part of the urban area of Grand Forks. Larimore is a city in Grand Forks County, North Dakota, United States.  It is located 3 miles south of the junction of US Highway 2 and North Dakota Highway 18.  It is part of the "Grand Forks, ND-MN Metropolitan Statistical Area" or "Greater Grand Forks".  The population was 1,346 at the 2010 census.  Larimore was founded in 1881. Grand Forks is the third-largest city in the State of North Dakota (after Fargo and Bismarck) and is the county seat of Grand Forks County.  According to the 2010 census, the city's population was 52,838, while the total of the city and surrounding metropolitan area was 98,461.  Grand Forks, along with its twin city of East Grand Forks, Minnesota, forms the center of the "Grand Forks, ND-MN Metropolitan Statistical Area," which is often called "Greater Grand Forks" or "The Grand Cities". Cities Area Transit (CAT) is the public transportation system in the neighboring cities of Grand Forks, North Dakota and East Grand Forks, Minnesota.  The scheduled transit bus routes are operated by the city of Grand Forks and service is provided to East Grand Forks through a cost-sharing agreement.  Paratransit for those who are unable to use the regular bus under the ADA, and a service for seniors, are provided under contract by Grand Forks Taxi. "Greater Grand Forks" (officially the Grand Forks, ND-MN Metropolitan Statistical Area) is the name used by some people to designate the twin cities of Grand Forks, North Dakota and East Grand Forks, Minnesota, together with their surrounding areas.  The two cities lie directly across from each other on both sides of the Red River of the North, but Grand Forks, with a population of 52,838, is more than five times larger than East Grand Forks, with a population of 8,601.  The metropolitan area includes all of the related two counties in the two states: Grand Forks County in North Dakota and Polk County in Minnesota.  As of the 2010 census, the MSA had a population of 98,461, and in 2014 estimates placed the total population at 101,842. Grand Forks International Airport (IATA: GFK, ICAO: KGFK, FAA LID: GFK) is a public airport five miles (8 km) northwest of Grand Forks, in Grand Forks County, North Dakota.  GFK has no scheduled passenger flights out of the country but has an "international" title (like many other airports) because it has customs service for arrivals from Canada and other countries. Knox County Regional Airport (IATA: RKD, ICAO: KRKD, FAA LID: RKD) is a county owned, public use airport in Knox County, Maine, United States.  It is located three nautical miles (6 km) south of the central business district of Rockland, Maine.  The airport serves the residents of midcoast Maine with commercial and charter aviation services.  Scheduled airline service is subsidized by the Essential Air Service program.  It is also a major hub of freight and mail service to Maine's island communities including Matinicus, North Haven and Vinalhaven.
Answer: Grand Forks International Airport