North Forest Overview - Baldur's Gate 2
This zone is unlocked during Chapter 6 of the main story after you escape from the Underdark. In order to access this zone you'll first have to pass through Small Teeth Pass then you can pass through this zone on your way to the Forest of Tethir. As far as I am aware you can exit out of any direction in this map (except North) to unlock the next one.
Much like with the previous Small Teeth Pass map this one will have different enemies depending on the time of day. During the day you will find significantly easier enemies that will be worth a lot less EXP and during the night you'll find much harder enemies worth more EXP. You should be able to rest on this map and clear both sets of enemies if you want all the EXP.
Headstone: You will find some random loot inside this headstone and it will sometimes be guarded by Genie or Vampire enemies depending on the time of day. I usually get a high level spell scroll from inside this headstone.
Adventurer Group: At this location you'll find a group of adventurers which drop various magical items. I recommend you buff up before challenging this group as they can be difficult if you run in without a plan. Mace +1, Mage Robe of Cold Resistance, Dagger +2, Platemail +1 and Two-Handed Sword +2