What if 30 portals to parallel universes suddenly appeared in cities around the world?

JULY 24, 2021

30 portals to parallel universes suddenly appear in 30 separate cities around the world.

These portals look like huge, circular areas of shimmering air (like that around a campfire), through which the other universe can be seen.

These portals are large enough that the world’s largest passenger jet could be wheeled through.

These portals are traversible. We can enter them and cross over to the alternate reality, and denizens of the parallel worlds can enter our world (and potentially enter any of the other portals).

Eventually, the various worlds are identified and catalogued.

In the comments, there’s a list of the various worlds and which cities their respective portals appeared in, separated by the type of world they are.

How does the world react to this event? How do you think our world would get along diplomatically with our new “neighbors”? What happens?