The date on the photo is February of 2010. The location is Moonglade and it's the Lunar Festival. The festival is ongoing right now so I dug through the archives for an appropriate photo. I have vague memories of participating in this in 2007. I started playing in October of 2006, so I'm thinking this was a holiday added from the beginning. I remember running Maraudon with a guild group to find the elder located there. Maraudon is so big. Back then, it was one continuous dungeon, not split like it is now. The elder was, of course, way down at the bottom of the instance. We got so lost.
Back then, there wasn't the bright yellow ! over a quest giver's head. You had to know where the elder was or you had to be willing, in 5-mans, to wander all over to find them. The bright white shaft of light was a dead give away to the presence of an elder, just finding that light was the issue.
For a new player, the Lunar Festival was your first visit to Moonglade, home of the night elf druids. I had no idea where I was on the map. It wasn't until the tail end of Wrath of the Lich King that I figured out how to run into Moonglade from Feralas or Wintersprings. Druids can hearth here and their primary trainers are here. The rest of us had to stumble upon the place ourselves following a road to see where it went.
Omen, the big white two-headed dog who is the "boss" of the holiday, has always been a unique encounter. WOWHead says Omen was added in September of 2006, with a small content patch. I remember this aura which would almost instantly kill anyone under level 60. If you could move fast enough, you could get away from it. And then there was the starfall. If Omen's aura didn't get you, the stuff falling from the sky would. You had to run away from him to get out of the falling stars. The aura is gone and he now has wolves around the area where he is summoned. Those weren't there originally. I remember when they were added, although I don't recall the year. They like to munch on lower level toons. Now days, Omen is an easy kill.
It's hard to make holiday bosses difficult. If you make them too hard, people coming to the holiday late in its run, won't be able to find a group to kill them. But I have to say that the ease with which Omen and his ilk can be dispatched is something of a downer, when my memories are of falling stars and instantly dying when my level 20 self ran too close to the big white dog.