Create a vector map and make user move through with three.js

Create a vector map and make user move through with three.js

I want to create several way maps that look like this, each map is use for
each level of my game, user (the camera) will move toward and backward
through a lines when holding the up or down arrow keys.
Please tell me the strategy to build custom vectors like this and make
user move thought this vectors only using three.js, (he/she can not go to
anywhere his/her want to)