Forbes Post Office. Situated in the heart of the Lachlan Valley, the Forbes Shire is regarded as one of the richest primary producing areas in the state. The district's history of white settlement goes back to the 1800s, when John Oxley ventured through the region. A colourful period began with the discovery of gold in 1861, bringing tens of thousands of people to the diggings. Fabulously rich strikes were made, but the goldfields also attracted those who sought treasure by easier means. Bushrangers Ben Hall, Frank Gardiner and their respective gangs became notorious for their daring robberies in the district, and stories of their exploits have become part of local folklore.