Thiès, city, western Senegal, capital of Thiès Region, near Dakar. A leading livestock-trading and meat-packing center, the city is a road and rail hub in an area producing rice, peanuts, manioc, millet, and fruit. It has rail yards and repair shops, and alumina phosphate deposits are worked at nearby Palo. The city also contains a polytechnic school. In 1863 the French built a fort at a village on the site of Thiès, and commercial development ensued after 1885. Population (1994 estimate) 216,381.