A study project was established to delimit and map the area of intensive agriculture around the city of Sohar in the 9th-10th c. A.D., to describe the ancient water supply system, and to try to understand the medieval land use in general. The amount of land under cultivation during the 9th-10th c. was many times greater that under cultivation today. Study showed that water was supplied by wells and by surface and subsurface channels. -- AATA