There are two airports that service Beaver Creek, Colorado:

Denver International Airport and Eagle Regional Airport.

DIA is approximately 2.5 hours away from Beaver Creek, while Eagle Regional is only 30 mins.

Eagle Regional (EGE) is a much smaller airport, so visitors to Beaver Creek will likely be flying into DIA.

To learn more about the airports available to Beaver Creek visitors please see:
https://blueskylimovail.com/what-is-the-closest-airport-to-beaver-creek/