Yorke Peninsula, promontory of the south coast of South Australia, between Spencer Gulf to the west and Gulf St. Vincent and Investigator Strait to the east and south. Extending southward for 160 miles (260 km) from Port Pirie to Cape Spencer, it is 20–35 miles (32–56 km) wide, with a gently rolling surface rising to 400 feet (120 m). Sighted in 1802 by Matthew Flinders, it was named after Charles Philip Yorke (later Lord Hardwicke), then first lord of the Admiralty. The peninsula’s soils yield grain crops, chiefly barley and wheat. Other resources are salt (by evaporation), limestone, and gypsum. Wallaroo is a major grain-shipping port for the peninsula. A dry, sunny climate has encouraged the growth of coastal resorts.