Easy to enter those... They're noted on your map with a single torch. You just walk right on in. Each one will have a skyshard and a boss. Get them both (easy peasy because there are always other people there doing the same), then mosey on your way out. Even if nobody else is there, they're still easy.thats what i been doing I have not yet done any solo dungeon on this game As I don't know how to enter them