Completed my portal room + portal.
It's down a secured shaft, about 20 blocks below my mountaintop castle, in the center of a mountain. Once at the bottom of the shaft you are greeted with a steel door, the door can be locked from the outside and is then impossible to open from the inside until unlocked. Once past that door you enter the observation room, a room overlooking the portal istelf. In the case of emergency where the glass is broken in the observation room, the portal room is automatically saturated in water to drown anything that may be in there, this can also be triggered manually from the surface in my castle. After leaving the observation room, you enter the armory. The armory is a secure zone, lined in obsidian rings around the smooth stone walls and inside it there are 2 chests - one containing 3 suits of armour (2 leather, 1 steel) and the other containing 128 arrows, 2 bows and a few swords.
I think I overdid it.
But I had nothing else to do at the time so w/e.
Poll