The flight distance from Denver International Airport (DEN) in Denver, United States to Kefallinia Airport (EFL) in Kefallinia Island, Greece is 9,703 kilometers (6,029 miles / 5,239 nautical miles). The estimated flight time for this route is approximately 12h, flying northeast at a heading of 40°.

This is an ultra-long-haul route, one of the longest in aviation. It requires wide-body aircraft with extended range capability such as the Airbus A350-900ULR or Boeing 777-200LR. Passengers should prepare for an extended flight with multiple meal services.

This is an international route connecting United States with Greece. It is an intercontinental flight between North America and Europe. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 02:01 in Denver, it's 11:01 in Kefallinia Island. With a 9-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

There is a significant elevation difference of 5,375 feet between the two airports. Kefallinia Airport sits lower than Denver International Airport. Travelers arriving at the higher-elevation airport should be aware of potential altitude effects.

The return flight from Kefallinia Island (EFL) to Denver (DEN) follows a heading of 321° (northwest). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the Denver International Airport (DEN) and Kefallinia Airport (EFL) detail pages, or use our flight duration calculator to compare other routes.