Icehouses (Pers., yakhchāl or yakhdān , "ice pit") were a feature of Iranian vernacular architecture. They are believed to have developed from covered earth pits in the first millennium B.C.E. to roofed structures in the eleventh/seventeenth century. They continued to be used until the late 1960s when they became replaced by modern refrigeration. Illustration 1. Domed icehouse at Abarqūh, Yazd province, Iran. View from west, dome and shading walls for ice-making basins. The height of the dome is 17 metres. Photograph courtesy of Hemming Jorgensen. Icehouses are