Yes you’re right, at that time I visited the art exhibition too (Pražský fantastický realismus v 60.let, it was nice too), that’s why I didn’t notice the entrance to the historic area was free. But it’s a shame if it’ll be closed down... :(
Yeah Prague is very impressive city, also I have lots of personal memories in it. And it’s also fun for me to write and share these memories in English :)