Chimp Caverns

Chimp Caverns is the sixth and second-to-final area in Donkey Kong Country. The humongous cavern filled with mines, including one filled with mist, is largely considered to be the hardest world in the game, due to it's overall high difficulty and length in levels in the area. The boss here is Master Necky Snr., a purple re-coloring of Master Necky, and has the same attacks and weakness as him, though his attack pattern is different. This is the last area with levels before the Gangplank Galleon, which goes right to the final boss.

In the Game Boy Advance version, it was drastically changed; it was changed to look like an area where mine carts on rails can be seen in a volcanic cave area.

Levels

 * Tanked Up Trouble: The first level of Chimp Caverns is no pushover. The level appears similar to Trick Track Trek from the previous world, but it is drastically different. While there is a similar layout, the moving platform now runs on fuel, that drains quickly. Fuel containers must be constantly recollected to keep the platform moving and go to the end.
 * Manic Mincers: A cave-mine area, this is considered one of the easier levels of C.C., but is still not a one-try pass. The level layout consists on a large abundance of spinning Mincers, all of which can be avoided with timing and skill. Spike balls are the main enemy here, and with practice, they will not be too much trouble. Gnawty and Krusha make appearances in a few parts of the level. Rambi is available early into the level.
 * Misty Mine: Misty Mine is, as per the name, a regular mine level with a thick layer of mist in it. Slippas are common pests in this level, as well as a few Gnawtys. Slippas are the most abundant, though. There appear to be no K-O-N-G letters at first, though there is a secret bonus room past the continue barrel containing them all in a rope-related mini-game.
 * Necky Nutmare: This additional level was only found in the Game Boy Color re-release of it. This level is a cave level, with a Mini-Necky infestation. Carefully time when the Kongs move on, for the Mini Neckies shoot nuts out in many unexpected places, such as before DK crawls under an area or is running down a straight path.
 * Loopy Lights: This is another mine level, with lights that are off at first, but must be turned on again by jumping into an ON/OFF barrel. Red Klap Traps make their appearance, where they are quite annoying, as they jump whenever the Kongs do, and usually walk in their path. An early bonus barrel can be found by jumping in the middle of the first pit. When the lights are off, the Klap Traps are difficult to see, so it is advised to keep the lights on as much as possible.
 * Platform Perils: Platform Perils is the last level of Chimp Caverns, and is by far one of the hardest levels in the game, if not than in Chimp Caverns. A Gray Krusha will greet the Kongs when the level first starts off, and even Donkey Kong cannot defeat it without a barrel. Vine Barrels, that do not roll, are the main weapon against them. The name of the level indicates platforms, and many platforms are indeed found in the level. The "perils" will happen when Kongs lose to the platforms going too fast for them, often going into enemies awaiting their attack.
 * Necky's Revenge: Necky's Revenge is the area ruler. Despite the level name indicating Master Necky returning, it is actually Master Necky Snr., a purple color swap of Master Necky. The only major difference is the fact that the boss here can launch a series of nuts and then be vulnerable for attack. In the GBA remake, however, Master Necky does appear alongside Snr. After this level is the Gangplank Galleon.