Cavern 37

 Cavern 37

One passage up and out. One middle passage in and two flanking, the left one further. Two right ones enter a chamber with a midstone. This is really one large chamber, with a couple radial passages and one offpassage and the leftmost coming up to meet. There is also a upbell and ledge near the top of the chamber. Vertical height is a cool cool 525 feet of dangerous plunges.

Here is the Midnight Manner edit.