In Black Desert Online Hystria Ruins is in between intermediate and end game difficulty grind zone wise. Hystria mobs are primarily grinded for money and the compass parts. The full compass when created allows a player see any where in the desert or the ocean. The compass also allows the user to port 5 players to you once every 10 hours. The xp here is decent but nothing special. With that being said, this spot is good for money. If xp is needed more than money Mirumock and Pollys forest will both be great for xp.
Hystria Ruins can only be accessed by portals in the desert. To the left is a video of what a portal looks like and what to do to use it. Down below will be a picture of where potential portals can spawn. The portals are at random spawn at locations within the blue circle. The Pilgrims markers are just showing where different Pilgrim sanctuary's are located these are not portal spawn points.