"The Great Barrow is not a place for weak hearts or frail limbs. Wicked wights and evil lords make merry in their terror. They've never caught Old Tom and never will they. He's the Master!
'If you be a-going, Tom will take you!'
You learned from the woman Andraste that the Lord of Nazgul was travelling to a place called Othrongroth. If you could spy on the Witch-king at this place, you might learn more of his plans.
Objective 1
'Well, my merry fellow! Ready to go a-leaping over barrows? Bring your friends and skip along. We'll sing a song that will make the Dark Ones rattle.'
[Travel Now: This is where you do the instance quest]
Objective 2
You and your allies braved the dark depths of Othrongroth and emerged victorious.