It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

how to get there from other locations
A quest a little more than halfway through the game will take you there. "Battle for Kaer Morhen"
You got to play the main quest until to get to it. You won't miss it, it will get you there directly, unlocking the travel destination from there on.