Czech Republic in July

Having to use up a few extra days of vacation before the change of fiscal year at work I have scheduled a 6 day vacation to Prague in the Czech Republic. It looks like a beautiful city and I will be staying right downtown. It appears I should have a few castles to visit in the region. I am sure that I will have a full trip for the 6 days. Of course I have the trip to Belgium for work followed by the stay in Bavarian Germany right after to go through first so I will probably have more information on Prague after that is done.