Many churches and synagogues line the city. I will not dwell on each one. You really must visit the Basilica of Saint Peter and Saint Paul. The basilica is worth the trip. You can also take a look at the Vysehrad cemetery. And finally, you can get a panoramic view of the city from the top of Vysehrad Hill.

More and more places are paying, I find it a shame. When you pay for a museum, I agree, but for a religious place, I don't find that very normal. Of course, that remains my point of view.