Hey guys. This is a map I'm working on for a story that I've mapped out. Now, obviously there are some things in there that need to be addressed.

1) The Green Blob in the northwest. This is supposed to be some sort of forbidden forest (or ghost forest.)
2) The Yellow blob in the south is supposed to be a military academy. The idea is that it's mostly a field where they simulate battles and such.
3) The Black Flags are supposed to be fortresses. (North to South Solaris, Exilium, and Reltan [and yes, Reltan is a fortress AND a city])
4) The Blue X's are ruined cities (North to south Krov, Arcis, and Trecis.)
5) The red line is where I want to put a canyon that will split that forest in half.

Now, the canyon is where I need the most help. I could use some ideas for how to show 1-4 for what they are, but I have no idea about the method of creating the canyon. I'd appreciate any help at all. Thanks so much, guys!