Klamath Falls is home to Klamath Regional Airport (Kingsley Field) located 5.5mi southeast of town. PenAir currently offers twice daily flights to and from Portland Oregon.
Of note, Kingsley Field Airport is also an alternate landing site for a space shuttle.
The next nearest airport is at the Rogue Valley International Airport over in Medford (MFR), which is about an hour and a half away. There is a daily shuttle to and from Medford, leaving from the train station and airport.
Commercial services to/from Medford are provided by Alaska/Horizon Air; United Airlines; Delta Air Lines; and Allegiant Air. These carriers offer approximately 60 arriving and departing flights daily to and from San Francisco, Portland, Seattle, Los Angeles, Phoenix, Denver, Las Vegas, and Salt Lake City. Rogue Valley International-Medford Airport also serves general aviation traffic, including extensive corporate and business travel.
Klamath Falls is located about an hour and a half away from Interstate 5 along OR-66 from Ashland. From I-5, OR-66 is accessed at exit #14. Likewise, if coming up from California one can also exit at US Hwy 97 from Weed, CA at exit #747 and continue northwards on U.S. Hwy 97. U.S. Highway 97 runs straight through the city and continues north to Bend, passing by Crater Lake.
The Amtrak Coast Starlight has an once daily train stopping in Klamath Falls on its way to Los Angeles in one direction and to Seattle in the other. The Amtrak station is at 1600 Oakes Ave (a block east of Spring ST) SE of downtown.