Sutter's Fort State Historic Park, 27th and L sts., was the first European outpost in the interior of California. Established by Swiss immigrant John Sutter after the receipt of a 48,000-acre land grant from the Mexican government, the fort's walls were 2.5 feet thick and between 15 and 18 feet tall. The settlement was initially known as New Helvetia (New Switzerland).
After the discovery of gold, Sutter's lands were virtually taken over by prospectors and he eventually left California. The restored, 1839 adobe fort contains pioneer and gold rush artifacts.