Monster Hunter: World's various biomes certainly weren't strangers to hidden areas, and lots of secrets. It's only fitting, then, that Monster Hunter World: Iceborne's Hoarfrost Reach would be host to some secrets of its own. One of the easier ones to miss would have to be its hidden path to the mountain in the middle of the map's summit; unless you know what to look for, chances are you won't even know that there's a path up to it. One of the expansion's numerous new rare endemic life can only spawn up there, so if you're going for 100% completion you'll need to figure out the way up to it sooner or later. You'll have to have progressed far enough into Iceborne's story to unlock the upper portion of the Hoarfrost Reach's map before you can even think of climbing the summit.
Reaching the Hidden Peak
The path to the summit is a little tough to explain in words, so we've taken the liberty to record a video following the path. Long story short - spawn into the Northeast camp, run over to Area 13, and then search for a hidden Wedge Beetle above the ceiling. You'll then be tasked with a few small platforming challenges to make it to an air vent that will boost you up the final ledge. Use the last Wedge Beetle to cross over onto the summit. The mountain has two sections to it, here - the bottom section which includes a small easter egg that series' veterans will find amusing, with a Rusted Kushala Daora husk, and a set of special mining points. On the other face of the mountain you'll find a wall that you can climb, which will lead to a trio of regular mining outcrops and a gorgeous view. This is also the same location that the Wintermoon Nettle will ocasionally spawn - one of a few of Iceborne's rare endemic life that guards a trophy/achievement.
Most of the time, however, the summit is just a neat little secret. Of course, that Rusted Kushala Daora husk certainly makes you wonder about what might be coming in DLC updates down the line! Only time will tell. Until then, Happy Hunting!