Have you been to Toledo? I have, with Spanish M. It's a really lovely city, and fascinating historically for the sort of reasons you're discussing here, and also a deeply sad place. I wonder if I'd have a similar reaction to some of the central European cities.

The first time I went there, the Transito synagogue was incredibly depressing; it was presented as, there used to be this religion called Judaism that died out 500 years ago, and this is what historians think it was probably like. That freaked me the hell out, but thankfully when I went back there a few years ago they'd sorted it out. It's now a normal Jewish museum, put together by people who know something about Judaism and mentioning that the religion still exists in contemporary times.