From the main cavern, cave divers can travel downstream for approximately 200 m/600 ft in either of two directions. These two downstream legs connect to the two primary resurgences at Running Springs. Explorers such as Woody Jasper and Sheck Exley tried to make the connection; no one has succeeded — or is likely to.
The upstream leg of the cave consists largely of one tunnel. There are, however, a few offshoots. These generally go only a short distance or loop back to the main line.
At approximately 240 m/800 ft into the cave, depths drop from the 21-24 m/70-80 ft range to 30 m/100 ft or more, depending on water levels. This means the likelihood of deco. Fortunately, you start offgassing as soon as you reach the shallower water near the cave entrance. You can also spend your deco time exploring the beautiful caverns.
Because of strong currents, a stretch of passageway from 120-240 m/400-800 ft has what Woody Jasper calls the “poor man’s scooter.” This is a piece of polypropylene line that parallels the main line. It gives divers something to pull on.
Cavern/Intro-level divers are prohibited from diving anything but the downstream side. To help protect the clay banks and other fragile formations, scooters are also prohibited.