Prague is an amazingly beautiful city, which will take you by surprise, however much you have read in advance.
Old Town Square is fabulous, one of those places where you can simply point your camera where you will - but you may prefer just to sit and watch. Lesser Town Square is less staggering in its proportions but still beautiful, and the castle is a knock-out. The bridges over the river are as romantic as those of Paris and none of the distances between sites is a barrier.
Particularly interesting is the Jewish Museum, not a single site but six in all, including the atmospheric Old Jewish Cemetery. The Old-New synagogue [oldest in Europe] is an extra. You might find the memorial Hall with its writings/drawings by the children in the death camps too emotive for you but you will appreciate the extreme beauty of the Spanish Synagogue.
Back in Christian territory, be sure to see the wonderful ceilings in the Strahof Monastery libraries further on than the castle on the 22/23 tram. [edit text][editors]