Is there a way to create an object that will teleport the user/main camera to another location when the user gets close to it?
Yes this can be done relatively easily by using Unity and Playmaker
1 create two objects, one of these will serve as your teleporter and the other as a destination in this case I'll just use two cubes and name them Teleporter and Destination.
2 add an FSM to your Teleporter object, then add two additional states
3 the first state will find the location of the main camera and store it as a variable
4 the second state will keep track of the distance to the main camera and the teleporter object, if it falls below a certain threshold it will trigger the teleport state
5 the third state: teleport will get the location of the Destination object, then move the main camera / user there
See the attached Diagram for details on the FSM setup
Also check out this previous answer to a similar question