There is an aesthetic option for viewing the Public Calendar that can include a Public Event image!
Go to Settings>Advanced>Public Calendars>Edit> then scroll to Default Calendar and you will see By Event as one of the options
Additionally, you will see By Event when viewing the Public Calendar
When clicked By Event, the user will see the Public Calendar with events displayed in chronological order
Notice unique images for some of the events!
When clicking on the name of the event, the user will see the event details with the image
To Add a Public Image, go into an event>Details and scroll down to Public Calendar Image and choose SELECT AN IMAGE