I should have done more research before booking this hotel. It was quite far from the heart of the city. There's a tram stop right across the street from the hotel, but it's a good 20 minute ride into town. The hotel itself was pretty nice. They had a really good breakfast. Staff was friendly, and you could buy tickets for the tram at the front desk. I would recommend staying here if you don't mind the distance from the city center. Like I said, the tram is right across the street (at the traffic light).
The heidelberg castle is amazing. Make sure and cross "Alte" Bridge and get picture of the bridge and the castle. I believe the famous picture of the bridge and castle is taken from "Philosophenweg", but you can easily get a good picture if you cross the bridge and walk a little ways.
You can take some sort of uphill train to the castle. (Look at the picture, I have no idea what they are called and was unable to translate) But, we missed out on going past the castle to the top of the hill. Wish we could have done that.
This was one of my favorite cities. Take a short boat tour, and relax with a beer.
