Teleporting Sanctum

As you cast this spell, a room fades into existence around you. The room is ten feet square, and appears to be made of the same materials (as well as being decorated identically) as your current surroundings, although no beneficial, detrimental, or magical effects are copied. If the space you currently occupy is ten feet square or smaller, the room that is created is a duplicate of the space. The room will have at least one door, regardless of how many doors are in your surroundings. 

At the same time as the room completes manifesting, you and anyone within 10 feet who fails a Wisdom save are transported to a location within 100 miles of your current location on the same plane of existence. If you are not perfectly familiar with the target location, your arrival is displaced by 2d10 miles in a random direction. The room appears with you at the location, with all doors affected by arcane lock which can only be opened by someone holding the key used as a material component. This key is not consumed in the casting.

Upon exiting the room it becomes clear that it is a freestanding structure which occupies a single 5x5 square and appears to be blue on the outside. The room will remain in place until either destroyed or the spell is cast again, at which point the room will fade out of existence at the same rate as the new room fades in.