Sigiriya, Sri Lanka
Sigiriya has a fascinating history: a civilization discovered the rock and then decided to build their city on top of it. The king was overthrown by his brother in a grisly betrayal, but then met his own death in an unfortunate way.
My mom and I went to visit this UNESCO World Heritage Site after Polonnaruwa, and even though I had the best intentions...I didn't make it to the top. I've been making great progress with my fear of heights, but there are still some obstacles that I am not yet able to overcome. I made it about halfway up the rock, and was able to see the really cool staircase that went up between huge lion paws, but beyond that was a rickety metal staircase up the side of the boulder.
I want to visit Sri Lanka again, and so hopefully I'll be able to work my way up to visiting the city on top of the rock.