Another Low-Tech Disappearing-Door Solution from Japan

Earlier we looked at this low-tech sliding shutter system from pre-industrial Japan:

Here's another design that does something similar, this one called otoshi-tobira (literally "drop doors" or "drop gates"):

This design isn't quite as old as the previous one; it's installed at the Gyōba Mountain Lodge, a way station for climbers and hikers that was built in the 1870s.