What are some cheap, fun travel destinations for a 21 year old to go on by herself?

Austin, TX, it’s cheap down there and lots to do for free… cool people, good cheap food at restaurants, affordable hotels, and of course, there is tons of music to enjoy down there! I guess this question really depends on where you live now/how much it would cost to get where you’re going… I hope where ever you go, you have a great time. It’s important to treat yourself after a long time of getting back on track. Good job!!!