ok i am sutck at the pandomuniom fortress an i get to the next way point

ok wen i walk out side an go down the stairs an theres a big open area it huge but there is no way out of it i have spent a 2 days looking throught it an cant not find any passageways or any way out plz help

There is an exit it just seems hard to find sometimes. It will be a little archway with some bone stairs leading up into the Plains of Despair (I think). From there it goes to the City of the Damned and then down into the River of Flame.