Welcome to Twain Harte After gold played out in the surrounding hills, many ranches lumbermills and orchards sprang up in the area then known as The Rock. In 1861 a road was built over the Sonora Pass and Twain Harte became a central point of commerce. See the Twain Harte Chamber of Commerce. Twain Harte Merchants Back to Sonora Map Back to Sierra Gateway Map