The castle is in a wonderful location with a breathtaking view of the city. There is so much history there. We've read a lot about it, so we didn't purchase the audio guide, and I was glad about that. I think those guides take the age and mystery away from a place. The admission charge was steep - 8 pounds per person, plus 3 per person for the audio guide.
The oldest part of the castle was built in the early 1100's, and is a small chapel commissioned by Queen Margaret. It was partly destroyed when Robert the Bruce had the castle burned instead of letting it go to the English. He felt bad about the chapel and had it restored. I can't tell you how it feels to walk in a building that old, and full of Scottish history, which we are both in love with.
We found a small sandwich shop off of high street, and purchased fresh sandwiches, drinks, and dessert for only 5 pounds! We needed that, because we have been over the budget constantly so far. We sat on the sidewalk and ate lunch, then walked high street some more. The shops there are definitely for tourists, full of kilts, wool, and Celtic jewelry. The street is small, and the buildings old and very tall. It's a romantic stretch of road, if you can look past the throngs of people walking and driving about.
WHAT TO DO with the rest of the day? If you have several hours, take a lovely stroll in the morning along the Waters of Leith to the Botanical Gardens. Then head to the castle and join the crowd. After that, Gladstone's Land is just a stone's throw away.