You find a cave at Lanayru Great Spring, near the Skyview Tower of the region.
Cave Location
This cave is located at 2851, 0474, 0328.
Explore the Cave
Go in and use Ascend to reach the ledge above. Then shoot the Bokoblins that are on the far ledge. From here, before you continue, use Ascend near the edge to reach the tunnel where you find this cave's Bubbulfrog.
Then glide down to the area below, and move a wooden board under the ledge where the Bokoblins were. Stand on it and use Ascend.
Then go back down and move the other wooden board onto the ledge above (you can tilt it to push it farther), then use Ascend again to go up to where you put the wooden board. Place the wooden board onto the water up ahead so you can use Ascend on the large flat stalactite above you. This leads to the top of a hill where there is the Upland Zorana Skyview Tower.