A wormhole that that can be walked through to get to another place at a maximum of 50 feet away. 

It will close after 10 Minutes but can also be closed earlier if desired. 

You need to knowledge of the exit point. If you dont know the exit point you must make a Intelligence Saving throw of 12. Or suffer 1d6 blunt damage and be knocked prone.

Later if casted at level 16 the range can be increased to 100 feet.

To Cast it. You need the ability to cast atleast 1 spell