What is the longest non-polar glacier in the world?

The longest non-polar glacier in the world is the Fedchenko Glacier.

Fedchenko Glacier is in the Yazgulem Range of the Pamir Mountains in Tajikistan. It extends for roughly 77 km, making it the longest glacier outside the polar regions. The glacier occupies a high mountain valley and is fed by numerous tributaries descending from the surrounding Pamir peaks.

Its great length reflects the geography of the Pamirs: abundant high-altitude snow accumulation feeds a long, narrow trunk glacier that flows through steep terrain. Fedchenko’s ice can reach around 1,000 m in thickness, and estimates place the volume of the glacier and its tributaries at about 144 cubic kilometres.

Siachen Glacier is a common mix-up because it is also exceptionally long, measuring about 76 km in many commonly cited estimates. However, Siachen is in the Karakoram and is still slightly shorter than Fedchenko. The phrase “non-polar” excludes the much longer ice streams and glaciers of Greenland and Antarctica.