The Sonoma Plaza was designed 150 years ago by Mariano Vallejo, the Mexican Governor, and is now a National Historic Monument. There's an eight-acre park with stately trees, and paths for people to walk. In the center you will see City Hall, and surrounding are loads of shops and restaurants. Many events are held here throughout the year, including the annual Ox Roast. Many people from around the world visit here to see the charm that is Sonoma.