For me it's:
1. Lufaise Meadows - The scenery, the lightning, the music. Such a beautiful place. First spot I checked out during a sneak preview of Promathia during the very first Vanafest. It was held at a small internet cafe here in norcal at The Great Mall in Milpitas. I even won a raffle for a Vanadiel clock that day.

2. Sanctuary of Zi'tah - Growing up in California, I have a deep love for redwoods. The trees and music here were both incredible. I used to come here sometimes just to hear the music long before I was able to level up in <Moon>.

3. Rolanberry Fields - Music and scenery again. This was where I popped up on my first journey to Jeuno where my friend and I were saved by a suicidal level 40ish Samurai named Celestine (yes I still remember his name!) when we got uber aggro. He rounded up all the mobs and died protecting us so we could complete our journey there at way too low of a level. I always waved to him whenever I saw the guy for years after that event.