Ghosts in the Dark

I played a Worgen character in Darkshore, and, on the advice of another player, I jumped into the Maw of the Void (the really big whirlpool in North Darkshore) and I was "sucked down the drain" to another area. I got the Going Down achievement on entering (due to the drop). There is a Cenarion Circle druid sitting there. Ignore her for now. Go up the embankment, fight a few undead, then you will see a Demon Hunter at the top. Kill him and he will drop a quest item that gives a quest to go to Ranger Glynda Nal'shea in Lor'Danel. Upon turning it in, the achievement will be gained. I have it on my worgen hunter.
I wonder if there is a Horde equivalent. Anyone know?

This will probably never come up for anyone else, but... I jumped in the maw while exploring as a horde character. Now several months ago I was sitting around bored in Org, and decided to kill the Cenarion Circle NPC near the flight master's tower. So when I fell down here I was unfriendly with Cenarion, and thus unable to leave this cave without hearthing

Moral of the story; It's probably a bad idea to go to war with cenarion circle

The whirlpool is located at around 53, 32 and is called "Maw of the Void". Jump in, you'll experience a short cinematic and end up in another area. Work your way up and kill the last mob, loot its quest item and start the quest. Go back down, talk to the NPC standing around where you came in to go back. Turn the quest in Auberdine and get your achievement!