The cheapest place to park at Denver International Airport (DEN/DIA) is typically the 61st and Peña Boulevard lot, which currently charges $7 per day. This is an off-site solar-powered lot located along the RTD A-Line commuter rail; you must pay for a train ticket (approx. $10.50) to reach the terminal, which takes about 11 minutes. If you prefer to stay on airport property with a shuttle, the Pikes Peak and Longs Peak shuttle lots are the next most affordable options at $8 per day. For those looking for even lower rates, off-site private lots found through apps like SpotHero (such as the Aloft Hotel or specialized airport parking lots) can sometimes offer rates as low as $4 to $6 per day depending on the season. Always check for "Early Bird" online booking specials, as the on-site "Economy" lots and "Garages" are significantly more expensive, ranging from $18 to $30+ per day.