This remote forest used to lie outside the domain of Rashemen, (but now is within the region as of 14th century DR) its dark and bitter woods are the home of angry spirits, hostile plants, and evil fey.
The secret sisterhood of the Durthans, aggressive counterparts of the Witches of Rashemen, use the Erech Forest as their private refuge, just as the Witches use the Urlingwood. The Durthans invisibly travel to and from the Erech to meet with their sisters, train guardian beasts, and explore dark magic. Assassin vines, night hunters, owlbears, shambling mounds, and at least one gray render guard the forest, in addition to telthors. Most dangerous are the Durthans themselves, who slay any intruders. Few people suspect the existence of the Durthans and fewer still know of their base in the Erech, so it remains secure against concerted investigation. The Durthans built a fortress for themselves, dubbed Citadel Tralkarn, but it fell during the Witch War of Rashemen in 14th century DR.
Falls of Erech
These falls mark the northwesternmost part of Rashemen. As the waters of the River Erech flow toward Lake Ashane, they plunge over a hundred feet in a roaring cascade of white that is breathtaking. Rashemi youths about to leave their country on a journey of adulthood camp here for at least one night and cast offerings into the falls to the spirits and deities. The falls are said to possess a magic that punishes thieves and rewards those who show the proper obeisance with good fortune and long life. Most Rashemi attribute any success in life to proper offerings.
Over the centuries, a fortune in gems, coins, weapons, armor, and minor magic items has accumulated at the bottom of the cataract. However, only a fool would try to steal this wealth. The water is glacial runoff, little more than freezing, and it's constantly pounding on the rocks below. As well, the local spirits guard these offerings and slay any would-be thieves. The Rashemi themselves capture and execute any loot ers who manage to escape the spirits.
Beyond the falls are a few humanoid tribes, but they rarely are brave enough to tempt the wrath of the Rashemi, instead harassing the small Nar horse tribes to the west.