In the Sahrawi refugee camps in Algeria, some unusual round bottle houses are dotted among the typical adobe structures that house the thousands of people who have lived there since they were displaced in Western Sahara more than 40 years ago.

These homes, built with recycled plastic bottles filled with sand, were the brainchild of Tateh Lehbib Barika. But it was really an accidental brainchild, as it turns out.