Nestled in the Rock River Valley, just 3 miles south of the town of Oregon, lies a 2,291-acre wooded area that is one of Ogle County's most beautiful and historic sites. Its scenic qualities come from 120-foot bluffs along 3.5 miles of riverfront forested with hardwood and pine trees. The history stems from the individual who, in the early part of the 20th century, augmented the natural hardwood forest by planting pines. Frank O. Lowden (1861-1943), Illinois' governor from 1917-1921, ardently embraced proper land use and strongly believed in reforestation as a way to retard soil erosion. Over several decades, an estimated 500,000 trees were seeded directly by him or under his supervision.
Since 1992, the tract has been known as Lowden-Miller State Forest. But prior to that Gov. Lowden and his wife, Florence Pullam Lowden, called it Sinnissippi Forest. Sinnissippi is from American Indian terms meaning "rocky river" or "troubled waters." It was part of a large and diverse farming operation that incorporated not only native hardwoods but pasture and sandy farmland. Because the soil was of limited use for crops. Lowden experimentally planted white pines and other tree species to see what would grow productively. The earliest plantings of white pines occurred before 1910 and are believed to be the oldest in the state.