Portals!

Portals are an important mode of transport at The Academy of Omniosophical Arts and Sciences, both for traveling to other dimensions as well as in and out of the elemental estates, and each element has its own unique and harrowing portal system. Do please post a portal pic you fancy. Portals are everywhere, you know. You just have to look for them ;)

Here's a snippet of Pete Trench from Dimension Q's first experience with a portal:

Pete took another deep breath, closed his eyes, and thrust his quaking arm down the hole. The tight clamping sensation on his flesh let him know there was indeed something there, and it had Pete in its grasp.  
Then it pulled … hard.