The following are Story Arcs from quest series found throughout Northrend in World of Warcraft: Wrath of the Lich King. We hope it is quietly informative to you.
Diary of High General Abbendis (Scarlet Onslaught)
Unlocking Northrend Flying Mount (Quest Tour)
Avatar of Freya (Daughter of the titans)
Battle for Undercity (Alliance)
Battle for Undercity (Horde)
Saurfang and Garrosh in Warsong Hold (Borean Tundra)
Brann Bronzebeard and Loken (Ulduar)