minecraft

Caves or caverns are naturally-formed cavities in the Overworld and less prominently, the Nether. Most caves have tunnels branching off as catacombs and winding in all sorts of directions. They are often very deep and can go from the surface all the way to bedrock. Caves are not ravines but will often lead into them. Because they mostly lack illumination, they will often have groups of hostile mobs like skeletons, zombies, spiders and etc.

One should never go into a cavern without a good supply of any lighting and weapons. Leave all valuables back in a safe place on the surface. However, if these valuables are from the cavern itself, make sure to have a chest to put them in.

Caves are huge and can have numerous intersecting tunnels, making them easy to get lost in. Getting lost in a cavern can be very dangerous, since getting lost in a cavern for too long may easily drain your hunger, saturation, weapon and armor durability, leaving you hungry and vulnerable to attacks, both of which could cause your death.

Finding caverns

There are many ways to find caves.

Exploring surface
By exploring the surface of the map, there is a good chance that an exposed cave will be found. Surface aquifers may indicate the location of a potentially-expansive cave system, and azalea trees will guarantee a lush cave below.
Digging
Digging around might uncover caves, but it is not easy as the map is (very) large. Choosing a random location and digging a tunnel straight down will intersect a cave system roughly 40% the time, but is not recommended since mining straight down may cause the player to fall in lava, a deep underground cave, or a cave system full of mobs. A diagonal tunnel (downward staircase) takes 3 times as long to dig, but is much safer and can be traversed both ways. Make sure to look out for dripping water or lava above you as it may hint at an aquifer or a lava lake.
Listening
By following the source of ambience, or the sound of mobs coming from underground, there is a great chance to find a cave. It's also useful to follow sound of water and lava.
Piston
Dig down, place a piston and power it. Since pistons don't extend if there are 13+ blocks ahead of them, you can use pistons to find caves.
The Nether
Traveling to the Nether, going down roughly 20 to 30 blocks, along by at least 16 blocks, and creating a new portal will likely cause the new Overworld portal to spawn in a cave since a portal is spawned in the nearest suitable space for the portal.
Cartograph
Use 3rd party software (such as cartograph) to make maps of caves. This can easily lead the player to dungeons or caves.

Recommended materials

These are some of the recommended items the player should bring with themselves into caves.

(Water) buckets - Empty buckets stack (while water or lava buckets don't), but the player will want to keep at least one bucket already filled with water. This is useful for turning lava into obsidian, allowing it to be safely walked on or mined. Note that there can still be lava below it though, and the water should keep flowing. This also useful for extinguishing themselves when on fire. Empty buckets can let the player move water or lava springs out of their way, or collect more water or lava for their own purposes. Water buckets can also function as a ladder, and are needed to capture mobs like the tropical fish and axolotl. Lava buckets are also useful for fighting mobs, especally for slimes.

Exploring tips

Navigation

Bring a compass.

It is surprisingly easy to get lost in caverns. Below are a number of methods the player can implement while exploring to prevent this, especially trail markers. The navigation tutorial has much more information about markers and other navigation methods. (Summary: Torches, wool, signs, blocks (which can be placed in "arrows", and especially jack o'lanterns.)

One fairly easy marker method is the "torch on the right" rule. While exploring a cave simply place torches on the right side of the wall as players go deeper in. This way, no matter how complicated and even intertwined the caves get, you can always find their way back because if the torch is on the left of a cave wall, that means they are heading towards the exit. Conversely, if it's on the right, it means they are heading deeper in.

Another tip is to use markings such as colored wool, or other blocks, to find where the player came from. The player can also put signs for further clarification, pointing to the direction in which they came from. Optionally, they can make an arrow shape with the blocks themselves.

Also, a player can place magenta glazed terracotta to place on the wall or floor as it has an arrow pattern on it. This can help show which way is the exit.

While it will not help the player in navigating the cave itself, it may be wise to bring a map with them into a large cave, should the player get lost and need to dig the way out. Note that most caves occupy less area horizontally than they might seem, but interconnected caves and mineshafts can sprawl over huge distances. The player might well map some new surface as the player is exploring underground, but the cave itself will not be mapped.

Cave survival

Caves can be very dangerous - the light level is dark enough for monsters to spawn, gravel is very common, which could suffocate the player, and the player will see lava often, especially in deeper caves, which can kill the player very quickly and burn dropped items. Here are some tips to help with surviving in caves:

Other tips

Here are some general miscellaneous tips that can help you when exploring caverns:

Exiting

When finished exploring a cave, it is best to try and find the way back to the surface via the way they have came, rather than by digging upwards. However, if need be, they can make their own exit — just dig upwards to the surface in a staircase fashion, watching for drips. Players can also dig directly upwards, however, be careful when doing so, as gravel could fall on you and cause suffocation. If this happens, you can use a shovel to quickly dig your way out. You should also keep an eye out for water droplets or lava droplets falling from the block above.

When digging a staircase out of a cave, it can be useful to check your map to figure out where you will, or want to, emerge. Coming out into the seabed can be tricky, especially if your torches get washed away. Put your torches 3 blocks up instead of 2 or 1 to avoid "wash-outs" (specifically: high enough that the air 1 block above the next higher stair isn't beside the torch).

Like mentioned previously, if you found a water flow that leads up to the ocean surface, you can use this to exit the cave. One can create easy access from the cave to the ocean surface by making a pillar of sugar cane. This will provide a fast, breathable path in both directions. This method can be used for both entering and exiting caves.