​Mt. Aventine Mansion

The Chapman family occupied their Mt. Aventine mansion until 1914, when the family estate was sold. This grand manor house was built by Nathaniel Chapman’s great-grandson, Pearson, around 1840, after a fire damaged the original house near the river. The 19th Century mansion, which commands a prominent overlook and spectacular view of the Potomac River, was appended to a small stone cottage dating to the late 1700s. Today’s structure includes several additions.

The structure was enlarged around 1860, expanding its east-west axis. The Mt. Aventine Mansion is a two-story, common bond brick structure, with lower flanking wings. A cedar lined lane provides the approach to the manor house.

The house currently consists of eight fireplaces, five bedrooms, six and one-half bathrooms, a front parlor, a dining room, a main kitchen area, a warming kitchen area, and two offices. There is also a basement under the main part of the house. The central hall with two wings architecture makes it one of the best examples of 19th Century homes in Southern Maryland. As such, Mt. Aventine was added to the National Register of Historic places in 1996.

From 1914, when the Chapman family sold its estate, until the 1990s, there were various owners of the property – including the Countess Margit Bessenyey, who owned the property from 1954 – 1984. The Countess was the late wife of the Hungarian ambassador to the United States and an avid equestrian. She used the Chapman property as a stud farm for Hungarian thoroughbred horses. Chapman State Park still includes the barns, stables, and a riding arena installed by the Countess.

Mt. Aventine Open House

The Friends of Chapman State Park host an open house every Sunday between April and September. These open houses feature guided nature walks, history presentations and children’s activities.​