Mount Gustaf is a location found in Breath of the Wild.
Breath of the Wild
Mount Gustaf is located southwest of Hyrule Castle, just east of the Regencia River and southeast of the Carok Bridge. On the mountain itself, Link will find some Warm Darners flying around, with the occasional enemy ChuChu appearing. At nighttime some Stalmoblins appear in the surrounding areas. The area just east of Mount Gustaf is rather dangerous as a Guardian Stalker patrols there.
There are some ruins to the north with a Guardian Skywatcher paroling the area. Near the ruins are some boulders on the side of the mountain and when blown up, there is a small rock with a Korok underneath it.
Just to the west of Mount Gustaf, there is an unnamed bridge that extends across the Regencia River. The bridge is heavily guarded with Blue Moblin and Bokoblin who shoot Fire Arrows at Link when he draws near. There is a camp just beneath the bridge as well, and once Link defeats all the enemies, he can open the treasure chest to get a Feathered Spear. A treasure chest is found in the water, just west of Mount Gustaf and it contains a Purple Rupee.
From the unnamed bridge heading eastward, there is a semblance to a pathway that was once more traveled. It extends over Mount Gustaf, connecting with the main path just to the east.
Nearby Korok Seeds
Bomb the rock pile and pick up the rock that was hidden underneath.