To see this calendar in your Google Calendar, log into your Google account (e.g. GMail or Calendar) and open
https://calendar.google.com/calendar/u/0?cid=aWx3YWNvaGxjQGdtYWlsLmNvbQ
This should end up on your existing calendar page with a pop-up confirming that you want to add the Hook & Ladder calendar. You will see it on the list of calendars on the left sidebar, and you can hide it, change its colour, etc.
To add events once to Apple calendars and other calendars that can accept ics files, download
https://calendar.google.com/calendar/ical/ilwacohlc%40gmail.com/public/basic.ics
To receive future events in an Apple calendar, follow the steps in robots.net