I have been to a number of mosques in different countries. Some were off limits to non-Muslims so I could just admire them from outside; some did let me enter. Some are very beautiful, some are simple, but my general feeling from them is one of peacefulness. You are welcome to visit Jewish synagogues in your explorations too!
@PiecingBabyFaceTogether I found an article from a couple of years ago saying that there are no active synagogues in Egypt anymore but that at least one of the old synagogues, the Ben Ezra Synagogue in old Cairo, is open for tourists.
