Elmira/Corning Regional Airport (IATA: ELM, ICAO: KELM, FAA LID: ELM) is a county-owned public airport in Chemung County, New York, seven miles northwest of Elmira and eight miles east of Corning.
 It is in the town of Big Flats but its mailing address is Horseheads, New York.
 The airport was formerly Elmira Regional Airport.
Ottumwa Regional Airport (IATA: OTM, ICAO: KOTM, FAA LID: OTM) , formerly known as Ottumwa Industrial Airport, is a public airport located five miles (8 km) northwest of the central business district of Ottumwa, a city in Wapello County, Iowa, United States.
 The airport is owned by the City of Ottumwa and is operated by the Airport Advisory Board.
 It is listed as a general aviation airport in the National Plan of Integrated Airport System (NPIAS) and as an Enhanced Service Airport in the Iowa Aviation System Plan.
Tri-Cities Airport (IATA: PSC, ICAO: KPSC, FAA LID: PSC) is a public airport 2 miles (3 km) northwest of Pasco, in Franklin County, Washington, USA.
 It is the fourth largest commercial airport in the state of Washington, and has two runways.
 PSC covers 2,235 acres (904 ha) of land.
Montrose is a station on the Chicago Transit Authority's 'L' system.
 It is situated between the Damen and Irving Park stations on the Brown Line, which runs between Albany Park on Chicago's Northwest Side and downtown Chicago.
 It is an elevated station with two side platforms located at 1817 West Montrose Avenue in the Ravenswood neighborhood of Chicago's Lincoln Square community area.
Pensacola International Airport (IATA: PNS, ICAO: KPNS, FAA LID: PNS) , formerly Pensacola Gulf Coast Regional Airport and Pensacola Regional Airport (Hagler Field), is a public use airport three nautical miles (6 km) northeast of the central business district of Pensacola, in Escambia County, Florida, United States.
 It is owned by the City of Pensacola.
 Despite the name, this airport does not offer direct international flights.
 This airport is one of the five major airports in North Florida, others being: Northwest Florida Beaches International Airport, Destin-Fort Walton Beach Airport Tallahassee International Airport, and Jacksonville International Airport.
Tri-Cities Airport (ICAO: KCZG, FAA LID: CZG) is a village-owned, public-use airport located three nautical miles (6 km) southwest of the central business district of Endicott, a village in Broome County, New York, United States.
 According to the FAA's National Plan of Integrated Airport Systems for 2009–2013, it is classified as a "general aviation" airport.
Tri-Cities Airport (IATA: TRI, ICAO: KTRI, FAA LID: TRI) (also known as Tri-Cities Airport, TN/VA), is in Blountville, Tennessee and serves the Tri-Cities area (Bristol, Kingsport, Johnson City) of Northeast Tennessee and Southwest Virginia.
 The airport is governed by the Tri-Cities Airport Authority (TCAA) whose members are appointed by the cities of Johnson City, Kingsport, Bristol (TN), Bristol (VA) and both Washington County (TN) and Sullivan County (TN).
Grand Junction Regional Airport (IATA: KGJT, ICAO: GJT) is a public airport three miles northeast of Grand Junction, in Mesa County, Colorado.
 Owned by the Grand Junction Regional Airport Authority, it is the largest airport in western Colorado and third largest in the state, behind Denver International Airport and Colorado Springs Airport.
Pellston Regional Airport (IATA: PLN, ICAO: KPLN, FAA LID: PLN) , also known as Pellston Regional Airport of Emmet County, is a public airport located one mile (2 km) northwest of the central business district of Pellston, a village in Emmet County, Michigan, United States.
 It is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2017–2021, in which it is categorized as a non-hub primary commercial service facility.
Montrose Regional Airport (IATA: MTJ, ICAO: KMTJ, FAA LID: MTJ) is a non-towered public airport on the northwest side of Montrose, in zip code 81401 in southwestern Colorado.
 Its two runways are at elevation 5,759 feet (1,755 m).
 MTJ covers 966 acres (391 ha) of land.

Question: Whicn airport, Tri-Cities Airport or Montrose Regional Airport, is a non-towered public airport on the northwest side of Montrose?
Answer: Montrose Regional Airport