The Mayor of Bree received reports of a ghost in an alley, but none of the constables will investigate the rumour.
'Hello there, are you looking for work? I've received complaints that there is a haunted alley here in Bree, and none of my brave constables want the job of looking into the rumours!
'Now I'm sure it's nothing, but if you'll just take a look down this alley at night, it would help me prove to my constables that they are being childish. Just take the road south-east from here. A small alley will turn off to your right not far from the South-gate. Follow the alley to some old ruins, and you should find the place where the ghost was reported.
'Oh, if you actually do find a ghost, well...get rid of it somehow!'
The ruins the Mayor spoke of are in an alley not far from the South-gate, off to the right.
Mayor Tenderlarch has asked you to investigate the rumours of a haunted alley and put the concerns of the Bree constables to rest. He has asked you to visit the alley by night, as that is the only time the ghost has been reported.
The ring is hidden at a barracks gate, but there are no barracks in Bree. The shade also mentioned a black rock, however.
Perhaps if you locate this lost ring the shade spoke of, it can rest.
The shade's alley is near the South-gate, in some old ruins.
You should take the ring you found to the shade and see if that appeases it. The shade likely will only appear in the alley at night.