Why was South Australia difficult to settle beyond its cultivated southern regions?

Settlement beyond the southern regions of South Australia was difficult primarily due to the state's harsh environmental conditions. South Australia is the driest state in the country, and its vast interior is extremely inhospitable to most forms of permanent settlement.123

Key factors contributing to this difficulty include:

• Aridity and Erratic Rainfall: Only about one-fifth of the state receives more than 10 inches (250 mm) of annual precipitation. While the southern coastal zone enjoys a Mediterranean climate, rainfall in the arid interior is highly unpredictable.2
• Extreme Temperatures: The northern two-thirds of the state experience more than 110 days per year with temperatures exceeding 86 °F (30 °C), compared to 10 to 50 days in the southern settled zones.2
• Agricultural Failure: During the 1870s, settlement expanded into areas with dangerously low rainfall. These regions proved unsuitable for sustained agriculture, leading to falling wheat yields and severe economic distress during subsequent droughts.4

Ultimately, the interior was so challenging that the state's population became increasingly concentrated around Adelaide, with many outlying districts eventually being abandoned.5