I am trying to get a calendar that works with my own caldav server. I note that Calendar seems to have the basic stuff there, since it can talk to both Exchange and Google. But none of those options seem actually to work with caldav, even though some various posts online suggest it ought to be possible. Am I missing something? (This is a showstopper for me -- if I can't make the calendar work I ditch Linux again and go back to Mac OS and the incredibly good BusyCal.) The other answers don't seem to answer this question. I tried Evolution, but I don't need a mail client (I have mutt) and I wasn't even able to get through the mail configuration successfully (it hung and then there was some error about missing services), so I didn't get to the calendar.
Oddly, I tried California first, because I'd heard about it first, and it seemed that gave me a caldav login (but it dodn't work), even when I tried Calendar. But once I removed California the option was gone.
I sure hope it's possible to use caldav on Ubuntu! [edited to add]: This is on Ubuntu 17.10, freshly installed and updated.
Thanks for any help