If you would like to see the St Mary's events in your Google or iCloud calendar, or in any calendar application that accepts iCal links, you can do so using this link:
Select the link above (try a triple-click on the link to select all of it) and copy it to the clipboard either by right-clicking and choosing Copy, or by pressing Ctrl-C (Windows) or command-C (Mac). Some browsers (Firefox is one) may offer "Copy Link Location" or "Copy Link" instead of "Copy".
Then follow the instructions below.
To add the events to a Google calendar, read https://support.google.com/calendar/answer/37100
Follow the instructions at "Add using a link".
To add the events to an iCloud calendar, read https://support.apple.com/en-us/HT202361
Follow the instructions at "Set up a new iCloud calendar subscription on your Mac".
Other calendar apps may offer a similar option to use a link (or URL).