Yes you can, through ical, which is the basis of most calendars nowadays. Follow the steps below.
- Open your Google Calendar.
- Find the 'Other Calendars' on the bottom of your sidebar (left).
- Click the arrow next to the 'Other Calendars' and click 'Add by URL'.
- Enter this address: https://internationaldownhillfederation.org/events.ics.
- Click 'Add Calendar'.
- Open 'Calendar'.
- Go to File > New calendar subscription (or command, option/alt + s)
- Enter the address: https://internationaldownhillfederation.org/events.ics
You can then change name and color (optional). Be sure to change the location to 'On My Mac'.
Click ok and done.