Shurima

There is no indication to them being still present in the lore, since most of the new lore based Shuriman buildings arent pyramid like. Ezreals new lore should have confirmed this problem. Now if you count the Blitzkrank Poro Roundup game as a good indicator to the new visual representation of many of the Runeterran locations, then they may yet still be present in some way.

...this is the first I've heard of this.

Go on.