This guide shows you one or more of the best and most efficient routes to farm Icecap in World of Warcraft Classic and is exactly what you need if you want to gather materials yourself instead of spending your gold on it on the auction house. If Icecap is not what you are looking for, you may take a look at all available farming guides.
You need Herbalism 290 to gather this herb.
Icecaps can also be farmed in Alterac Mountains (the snowy part where the Yetis live), but the best zone to farm it is definitely Winterspring. You will also find a lot of Mountain Silversage here.
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