When I use this URL to make a redirection I get a page not found error.
The Url I end up with is this: https://sandboxname-customername.cs83.force.com/communityname/choose-current-dealer
What I did now is add an "s" in the url because this seems to be there for all URLs.
The Url I end up with now is this: https://sandboxname-customername.cs83.force.com/communityname/s/choose-current-dealer
And this works.
Now the question is if it is safe to hardcode an url like this or if it is likely to change in the future?