My world is old, since it existed before the Ancient Knowledge update. The update retro upgraded my world to have a wormhole that is supposed to take me there! But it does not work. It crashes my game and says it "lost connection to the server", and when I log back into the game, it takes me back to my previous save.
I know it's probably an old issue but I'm quite slow at this game.
I did it twice, just get in the wormhole next to the blue mushtree forest in my world.