User profiles have a "Calendar" item, but the behavior isn't very good. There are no query options, paging it doesn't work, etc.
For v0, this should probably just link to /calendar/?invited=epriestley or similar? I don't think we clearly gain anything by keeping it separate at this point.
Original Report
For example, https://phabricator.example.com/p/<user>/calendar loads as expected, but https://phabricator.example.com/p/<user>/calendar/2015/09/ will 404.
We don't need this fixed, but FYI since I noticed it ..