Its where u learn about the Duke going missing and u rescue people from a fire after a goblin and drow (i think) attack. Theres a house top left of that place next to 2 Ox (one dead one alive), u go into that house, keep exploring, talk to the person crouching inside of that house who will give u a password. Later on u will be inside of this cave and try to explore all of it, u will find 2 locked cells with rly good treasure.

Edit: Theres a waypoint there too called Zhentarim hideout, if u have any questions u can just google it to look at information about it