According to the site below, it is 144.89 miles long and the second largest cave in the world.
yes
Yes, the cave is natural.
hope across all the poles in the cave its at the end
The red jewel is in a cave at the Mountains of the Moon, and you must beat an old man at mancala to enter the cave. (see related questions)
The Purple Jewel is at Blue Nile falls, in a cave behind a plant on top of a rock on the right side. You can only go in the cave once you help the woman across the falls with the animals. The Red Jewel is in the old man's icy cave at the Mountains of the Moon. You have to climb the trail and beat him at the Mancala game. (see related questions)
the red one
in a bush
Jewel Cave was set aside as a National Monument by Theodore Roosevelt on February 7, 1908.
First, go to nabooti island.(it's on the poptropica map). The white jewel is in the diamond mines. Blue is inside the tomb/pyramid whatever it is.At the waterfall there's a cave hidden behind a bush.One of the other jewels is in the cave. In the ice cave is a jewel and a cell phone. the last jewel is buried under the turtle at the kaya forest. And there you have it! Hope i helped. Bye!
level 3
just LOOK AROUND
Jewel Cave; currentlysecond longest cave in the world - 157+ miles of surveyed passages. NearCuster, in South Dakota's Black Hills. (Source: Google) The photographs of its show-cave section on one of the references show it to be a well-decorated karst cave,so it results from normal limestone-cave development processes; and if it contains streams, the stream-passages are still beingformed by those streams.