Maybe you know it already, but might be helpful for other readers, too: wheelmap.org
It’s an OpenStreetMap where users can mark if places/buildings are wheelchair accessible. You can filter the map to only show places related to tourism.
Also, at least in Germany, some cities/areas have accessibility guides that list accessible hotels, free time activities etc. – some probably in German only, though. So if you’d be interested in holidays in a certain city in Germany, I could look for such info.
The best country to visit when in a wheelchair is most likely the US. All public places have to be wheelchair-accessible, and nobody steals the designated parking spots.
What you want to visit depends on what you like most. There aren’t that many old cities, of course (though e.g. Boston and San Francisco are nice), but there are plenty of amazing museums, particularly in Washington DC. And of course there’s all the theme parks everywhere.
Credit:stackoverflow.com‘