Hidden Down Stairway

A horizontal 2x5 block door covers a hidden down stairway. When activated, the door blocks slide apart and the top step raises to form a stairway from ground level down. Can be used to hide an entrance to a dungeon or evil lab or treasure vault! Schematic includes a top level open button, and pressure plates at the bottom of the stairs to open from below.

Copied while standing on Emerald block in front of door facing East. I changed the door panels to prismarine in the schematic so it's easier to see the panels when integrating it.

A delay circuit closes the door after ~15 seconds. Includes an AND gate lockout so switch inputs can't try to open the door if it's already open (so won't confuse circuit). Very Stable.

The Delayed Deactivation circuit alone is available laid out flat in http://www.minecraft-schematics.com/schematic/11110/.

I copied this schematic out of a hidden door in a field so kept some of the grass, etc, as an implementation idea. The delay circuit sprawls horizontally, but could probably be moved below the door for a narrower but higher cuboid space. Probably needs some cleanup before final paste.

Enjoy!

Original Door/Stairs design by Nims (NimsTV on YouTube) "Minecraft Tutorial | Sliding Underground Base v3.0" https://youtu.be/JTdmrYgEITY?list=PLL8R1gMO8fLG9_2mixkO1aGCQNvtRZMRT. It does not include the close door delay circuit, but gives a great tutorial on building the door.

I think you could build a vertical door to an up stairway, but it would take some work to hide the door mechanism and other circuitry.