Hm. I would go with Stratholme. I loved the eerie feeling and story behind it. Back in time the loot fight for the key... Nostalgic. :)
Galhara form Reign of Azshara
The instance i miss the most is probably AQ40. Never got all the way through it before out guild decided to transition straight to naxx instead.
my favorite instance would definitly be hellfire ramparts cause of the fact that its the first place you charge at in outlands while in draenor it will be the last place you will face off against
My favorite instance is Gnomeregan
hmm my fav instnace would have to be wells of eternity i think
Scarlet Halls The hounds attacking their masters, scarlet treasurers literally dropping piles of gold, and a crazy pyro mage. I liked using the meat buckets to avoid killing the dogs but then we outgeared it and everyone just facerolled through the dungeon.
My fav instance is Karazhan
Ulduar: I liked the choice of hard modes.
Eternal Black Temple <3
Karazhan! Still the best instance/raid ever.
The Stockade, 'cause of Hogger. :PAs for raids, my favorite was Black Temple.P.S.: Finally a contest international users can participate in!
Icecrown Citadel, of course!
Stratholme will always have a special place in my heart thanks to vanilla. So many hours spent running that place.
Can't really decide which instance to name as favourite. I always liked the old UBRS, but from the instances currently ingame it is definitely Ulduar.
Storm Peaks, up in Thorim's room. It's just neat looking out into all those storms....
I think my favorite would have to be The Oculus.I hear so much hatred for it, but loved running it. I loved getting people the X Void achievements too. Close second would be Shadow Labyrinth. Time for fun!
That is a VERY hard question.... My all time favorite dungeon would have to be Mana Tombs. The Ethereals are definitely one of the most awesome races I have ever seen in a MMO. I only dream they become playable some day!