There is a great script on github: [BaconStringUtilsSlugifier](https://github.com/Bacon/BaconStringUtils) (you don’t need to use Zend to use the classes in `/src`.
It does not only convert chars like `ö` to `o` but also `北亰` to `Bei Jing`, according to the readme (slugified that would be `bei-jing`)… You never know, right? ;)
You then need to redirect requests to a common landing page (probably just `/index.php`, using .htaccess), read out the slug and query that page from a database (in which you have an indexed ‘unique, which is an index’ column with the slug to make queries fast).
The `html` extension in your example doesn’t mean there is an actual html file.