Where is your favorite place to vacation?
The question implies a place you'd keep going back to. We're inclined to go to new places all the time.
Apart from that, it's a tough question. My wife would say Venice. I have a soft spot for the island of Rhodes. As far as overall cultural experience it'd have to be North Vietnam.
Like I keep saying, I'm in my favorite place already..southern Thailand. But if money were no object, I'd go camel trekking again in the Australian Outback each year. And go camping in Tasmania again as well.
Photo is of me kissing "Sir Wobbles" - largest camel in the train, on the nose, from the back of my own, smallest camel, Alokah. She was captured by from a wild camel herd and afraid of men, so I was assigned her as my camel for the trip. I brushed her, tethered her out to eat, saddled her in the morning, and told her to kneel (Kush!) and/or stand up as needed.