I wish I had taken a picture for you. From memory though, the clothes lines have three walls so that the sight of hanging clothes is shielded. There is a concrete floor and no roof. I've tried to show this in changeset #106237810

I was quarantined here for two weeks in April. The huts and laundries are all labelled with their numbers.

Hi Ivan,
Thanks, I'm onto it. I had been looking for the proper way to do this, but had missed the link.
Regards,
Mike