On March 11, United Airlines began a new, single-ticket, plane-and-bus service to Breckenridge, and on April 1, the Chicago-based airline will start a similar four-times daily service to Fort Collins. The actual flights end at Denver International Airport, but from there (while still airside at the airport), you can immediately board a luxury bus (operated by Landline) connecting straight to the resorts, with your luggage directly transferred to the bus by the airline, hassle-free to you (at least in theory).