Italy Museum Pass

No, city by city only. Have you seen anything like this offered in other countries?

There are Heritage Passes in the U.K., for castles, manor houses, and historical sights, but I wasn’t aware of anything similar in Italy.

The Netherlands used to have one too (the Holland Pass) although I don't see it anymore. There's also one which covers 345 museums, castles and gardens in Germany, France and Switzerland too (not, say, the biggies in Paris or similar). I've never seen one for Italy.

Switzerland has a museum pass that's good for many museums in the whole country. It's included in the Swiss Travel Pass, which made this a better deal for me (as a stand alone, the Museum Pass is very hard to make pay off for most visitors).

Other than the British passes mentioned above, that's the only one I'm aware of. I've never seen such a thing for Italy.

I have no idea what passes are available now, but in the past when I've looked, it was hard to make the ones available for Florence and Rome pay off. Be sure a pass is a good deal for you before buying one.

The Louvre's annual pass covers a lot of sights around France--enough to substantially increase the value of the pass for some visitors traveling extensively in that country.

In Italy you are very luck if in a city you have a one ticket for all the museums. :-D
Often you must struggle between different ticketing and booking systems in each single museum. :-(