Tracking down Portcrystals in Dragon's Dogma 2 lets you expand your fast travel network and put down beacons so you can return to important quest locations at your convenience. There are only a few permanent Portcrystals in the game; most notably in Vernworth and Harve Village, but you can set up the portable variant wherever you want.
The more portable Portcrystals you acquire, the more elaborate your teleportation network can become. Of course, you'll need a Ferrystone each time you actually want to go somewhere...