Like many other Icelandic place names, Langjökull can seem a little difficult to pronounce. But the truth is that Icelanders will understand you even if you don’t get it exactly right. You can pronounce it how it’s written in English: lang-jo-kull.
But if you want to get it right, Langjökull can be broken down into three parts:
“Lang” is pronounced a little more like the English “lung”
“Jö” is a soft “j” sound, more like a “y”, followed by a long vowel similar to that in the French word “coeur”
“Kull” is pronounced like the English, but watch out for that double L. In Icelandic, it’s more like a “tl” sound, with a very soft T.