Hi from Wisconsin,
Been to Kutna Hora. (Hora as I recall means hill or top) As I recall there are two things to see, The Ossuary and St. Barbara's church. We spent parts of two days there. This was a while ago so things may have changed. Make sure you know where the Ossuary is located. The directions we had said it was across from the cigarette factory. Well the factory was inside and occupied a large church and the only identifier was a small sign that had PM on it. That would stand for Phillip Morris.
With Google maps this location mystery should be easy.
See where the bus or train drops you off in Kutna Hora. It could be quite a walk to either from where you get dropped. I am not a fan of tours, but the advantage is they will drop and pick you up real close to the front door of your destination. I like the adventure of the local transport systems and finding our way around on our own.
Students of mine have gone to Kutna Hora since I was there and they all enjoyed it.