October 23 is one of the historical public holidays in Hungary and as such, many opening hours are modified on this special day.
See the list of Budapest museums, Budapest attractions, Budapest baths, etc. here:
We suggest avoiding the national demonstrations and rallies that take place on this day, unless you are as curious as a photo blogger or an investigative journalist. That said, Budapest is not ‘closed’ on this day, and you will surely find interesting things to do on October 23, if you can do a day without shopping.