If you don't plan on renting a car, other options include shuttles from Denver Airport to downtown Estes at https://www.estesparkshuttle.com/DIA-airport-shuttle or potentially Uber/Lyft depending on availability. Uber/Lyft are potential options to get from the airport to Estes Park, but are unlikely going to be available to get you from back to the airport.

You also can take the A line train to Union Station in Denver, then take the Bustang up to the mountains. The Bustang has less availability, but will be cheaper. Please ensure you are purchasing the correct tickets for each leg of your trip if you choose this option.

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