In the land of the green they are taking refuge in some sort of stone ruins. The filming location is the Harris Woolen Mill Ruins in the Rockwood Conservation Area, about 30 miles west of Ontario. A popular tourist area.
Karen Glave (Marlene) has worked with Morgan Kelly who had played Alvis Akari in Killjoys. They both appeared together in the movie 'The Shape of Water', playing African American Wife and Pie Guy respectively.
The episode title "The Warrior Princess Bride" seems to a combination of "Warrior Princess" as in Xena: Warrior Princess (1995) and "The Princess Bride (1987)".