Denali's official height includes the ice on top.

"The summit" sounds obvious — until the highest point of a mountain is buried under permanent snow and ice.

On Denali, the top you can stand on isn't rock.

In June 2015, a survey expedition used modern GPS equipment and methods, along with a better geoid model, to determine a new elevation of 20,310 ft.

The team probed the ice cap to find the rock beneath it. They estimated the depth at about 13.6 ft, but could not definitively identify the rock summit. So the official elevation was measured to the top of the ice cap.

That's why we don't subtract 13.6 ft to get a "rock height": the ice depth is an estimate, and the rock summit wasn't located.

Official surveyed elevation · ice depth estimated. 20,310 ft is the 2015 survey result to the top of the ice cap. The 13.6 ft ice depth is an estimate, and no rock-summit elevation was established.

Measurement surface is the ice cap, not rock. Surveyors could not definitively locate the rock summit.

• National Park Service

  2015 Denali summit survey(opens external site)

• National Park Service

  Denali Summit Survey(opens external site)

  20,310 ft measured to the top of the ice cap

• National Park Service

  Denali Summit Survey(opens external site)

  2015 GPS survey; ice depth estimated at 13.6 ft; rock summit not identified

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