How to View and Hide Calendars on Your iPhone
You now have one or multiple calendars on your iPhone. Calendar neatly presents the data in four formats: in portrait (vertical) view, Calendar displays a year-at-a-glance, a month-at-a-glance, a day-at-a-glance, which displays the dates of the associated week across the top of the screen, and a scrollable list of your events and appointments.
Turn your iPhone to the landscape (horizontal) position to see several days at-a-glance — 5 on an iPhone 5 or later, 3 and a half on earlier models. To choose which calendars you want to see:
Tap Calendars on the Home Screen.
Tap the Calendar button at the bottom of the screen.
A list of your calendars opens.
Tap the name of the calendar you want to see or hide.
If there’s a check mark next to the name of the calendar, events in that calendar show up in the four views. Note that the Calendars are color-coded. Events shown in List and Day views are color-coded to respond to the calendar they come from.
Tap Show All Calendars if you want to see all events.
Calendars opens to the view you most recently used.