NOTE: Only iOS users are able to subscribe/unsubscribe to a team calendar using iCal.

  1. Navigate to your "iOS Device Settings".
  2. Tap Passwords & Accounts.
  3. Tap Subscribed Calendars.
  4. Select the "Calendar" from which you wish to unsubscribe.
  5. Tap Delete Account.
  6. Tap Delete Account once more to confirm.