Minecraft: Ancient City Redstone Door - Find & Open

Minecraft's Deep Dark biome and its Ancient Cities offer numerous rare and valuable treasures. Exclusive enchantments, music discs, and the recovery compass can all be found within these mysterious underground settlements.

Ancient Cities also hold a curious secret. Buried beneath the portal-like structure in the city's center, behind a hidden door, lies a room filled with redstone contraptions designed to teach players about technical mechanics. If you want to find and explore this secret room, here's how.

The Redstone doors within Minecraft's Ancient Cities are often overlooked, especially as they don't contain valuable loot. This guide provides more information on finding and entering this secret room.

Ancient Cities are sprawling underground structures that appear rarely in the Deep Dark biome. Each city's layout is randomly generated, featuring different structures, but all have a large portal structure at their center.

This portal is large, rectangular, and made of reinforced deepslate. In front of the portal is an altar-like area with candles, and a large staircase leading up to it. Two walls surround the portal area, with a trench-like channel between them, and walkways run from the city edges to the portal area in all four directions.

Understanding Ancient City layouts is crucial for locating the secret redstone room. This room is hidden directly beneath the portal structure and is divided into several smaller rooms, each containing a redstone build designed to teach players about redstone.

The redstone room is concealed by a secret door that uses pistons to blend into the wall. Fortunately, finding this door is relatively easy if you know where to look.

Approach the portal structure from the side with the altar, and then drop into the trench area between the two walls. Stand in front of the very center of the portal, underneath the bridge to the altar, and you'll see a recessed area in the wall. This is where the secret door is located.

If you want to immediately enter this room, you can simply tunnel in through the side. However, if you've never been here before, we recommend opening the door and entering the room normally, since the experience is the real reward.

If you want to do this, head to the rectangular platform under the portal and tunnel inwards.

Now that you know where the door is, it's time to get it open.

While the same large portal structure is always generated in every Ancient City, there are actually three possible variants for the redstone room hidden below, with each Ancient City generating a random one of the three.

The three possible redstone rooms are largely the same, but what differs in each one is the mechanism used to open the door. Given that the room is hidden, it's impossible to know which variant of the room you have, and therefore which mechanism controls the door.

The first mechanism is arguably the simplest. It uses a Sculk Sensor (which is submerged, preventing any noise and cluing players into the existence of the secret room) to control the door - as we'll see, this is a key component for all three mechanisms.

The Sculk is heavily covered in wool, making it difficult to make noise and activate it because the wool blocks the sound from almost every direction.

The only part of the Sculk not covered in wool is directly above, so go up to the altar and stand against the raised section on the left side facing the portal.

Jump up and down until you hear the pistons activate - the door will have opened, allowing you to head inside and explore the secrets the hidden room has to offer.

The only other parts of this circuit are a redstone lamp with a lever, which allows the door to be permanently opened from the inside and perhaps aims to teach players that lamps are solid blocks, and a pulse extender, which gives you plenty of time to make it down to the door once you activate it.

The second mechanism is a little more complex, as it aims to further teach players about comparators. It features a comparator, taking input from a furnace that's been very deliberately half-filled to a specific amount, feeding into another comparator in subtraction mode.

This subtraction comparator is taking its input from a Sculk Sensor, which is again how the door is to be opened. The comparator circuitry runs into a small circuit that will only allow signals of exactly one signal strength through - anything more, and the repeater will activate, shutting off the circuit.

The idea here is that you have to produce the right kind of vibration to create the right level of signal strength from the Sculk so that after the furnace's signal strength is subtracted, you're left with a strength of one.

The furnace emits a signal strength of seven, requiring a vibration that will output eight from the Sculk Sensor. There are several ways to achieve this, but the simplest is eating. Simply consume any food you have on hand, and the door should open.