He is known for several sculptures, including the Thomas A. Hendricks Monument in front of the Indiana State Capitol in Indianapolis, Indiana, the Actor's Edgar Allen Poe Memorial in the collection of the Metropolitan Museum of Art, La Penserosa (The Pensive One) in the library of Oberlin College, and the Drake Fountain in Chicago. John B. Drake, of Drake and Blackstone Hotel fame, commissioned Park to design the fountain to coincide with the 400th anniversary of Christopher Columbus' voyage to the New World. It is a Gothic Revival design with classical columns and figure, a cathedral-like steeple and a sculpture of a young Christopher Columbus. It originally dispensed ice cold water in four fountains. The structure was placed on Washington Street in front of the Chicago City Hall in 1892. It has been moved twice, it was restored in 1986 is in the South Chicago neighborhood.
In Milwaukee, Park sculpted the statue of Washington in the Court of Honor and the Solomon Juneau Monument in Juneau Park.
Local gossip has it that Elizabeth Plankinton, wealthy heiress to a meat packing fortune in Milwaukee, fell hard for Park after commissioning him to sculpt George Washington for the Court of Honor. They became engaged and her father built the couple a fabulous home, The Plankinton Mansion on Milwaukee's Grand Avenue. However, Park ran off with a dancer, and Plankinton was so heart broken that she never set foot in her fabulous home. (It was demolished 100 years after its construction to make way for Marquette University expansion.)