The Donald B., originally christened the Standard, is a historic sternwheel towboat located along the Ohio River at Ripley in Brown County, Ohio. Built in 1913 by the Marietta Manufacturing Company of Marietta, Ohio, the vessel was constructed for the Standard Oil Company of Ohio to transport oil barges along the Ohio River and its tributaries. The towboat features a steel hull, a traditional stern paddlewheel, and a wooden superstructure. In 1923, the vessel underwent a significant technological upgrade when its original gasoline engine was replaced with a three-cylinder, 100-horsepower Fairbanks-Morse "C-O" semi-diesel oil engine, which remains operational today. Renamed the Donald B. in 1940, the vessel continued active commercial service for decades, showcasing the durability and practicality of its design.

The Donald B. is nationally significant as a rare, remarkably intact survivor of the transition era from steam to internal combustion power on the inland waterways of the United States. As one of the oldest operational sternwheel towboats in the nation, it represents the small-scale, diesel-powered towing vessels that revolutionized riverine commerce and transport during the early-to-mid 20th century. Its 1923 Fairbanks-Morse engine is one of the last surviving operating examples of its type in maritime use. Because of its exceptional preservation and its contribution to American maritime and technological history, the Donald B. was designated a National Historic Landmark and listed on the National Register of Historic Places in 1989.

The John P. Parker House, situated along the Ohio River in Ripley, Ohio, is a site of national significance associated with one of the nineteenth century's most remarkable African American figures. Born into slavery in 1827, Parker successfully purchased his freedom, educated himself, and relocated to Ripley, where he became a highly successful industrialist, iron founder, and inventor. He established the Phoenix Foundry and built his two-story brick residence around 1853, living there until his death in 1900. Parker was one of the few African Americans to obtain U.S. patents before 1900, and his home and adjacent foundry site represent his extraordinary rise from bondage to prosperous, self-made business ownership in a highly turbulent era.

Beyond his industrial accomplishments, the house is globally recognized for its association with Parker's heroic and clandestine work as a key conductor on the Underground Railroad. Utilizing his home's strategic location on the border between the free state of Ohio and the slave state of Kentucky, Parker repeatedly risked his life and freedom by crossing the Ohio River to guide escaping enslaved people to safety. Collaborating with other local abolitionists like John Rankin, Parker is credited with personally helping hundreds of freedom seekers on their journey north. Designated a National Historic Landmark in 1997, the John P. Parker House stands as a vital monument to African American agency, resistance, and the dangerous fight against the institution of slavery.

The John P. Parker House, located on the banks of the Ohio River in Ripley, Brown County, Ohio, holds profound historical significance as the home of one of the most daring and active conductors on the Underground Railroad. Born into slavery in Alabama, Parker purchased his freedom as a young man and eventually settled in the bustling border town of Ripley in the late 1840s. Operating from this modest, two-story brick residence, Parker risked his life and liberty on a regular basis by rowboating across the Ohio River into Kentucky-a slave state-to rescue enslaved individuals and guide them to safety in the North. Working in tandem with other local abolitionists, such as Reverend John Rankin, Parker helped secure freedom for hundreds of fugitives, making his home a critical gateway on the path to emancipation.

In addition to its association with the struggle against slavery, the property is highly significant as the home of a pioneering African American industrialist and inventor. On the lot adjacent to his home, Parker founded the Phoenix Foundry, where he successfully manufactured agricultural castings and machinery. He was one of the few African Americans to obtain multiple patents in the United States before 1900, including patents for a soil pulverizer and a portable press. Listed on the National Register of Historic Places in 1980 and later designated a National Historic Landmark, the John P. Parker House stands as a powerful monument to Black resistance, self-determination, and industrial ingenuity in nineteenth-century America.