The design of the Oxford County Gaol is heavily influenced by the Italianate Romanesque style and includes a number of Tuscan Gothic details. This picturesque style was very popular in the mid-1800s, especially after the development of cast iron and pressed metal technology. The unified design with subtle detailing; the elaborate cornices; wide, overhanging eaves; and the tall, rounded arch-topped windows all add to the Italian Romanesque aesthetic. The Tuscan influence can be seen in the gently sloping hip roof. Moreover, the distinctive turrets and elegant, elongated windows of this building mimic the look and feel of medieval castles and help provide a fortress like appearance to the building.

A rear extension (kitchen) was removed in the 1980s reconstruction, but it is still evident that the Gaol was constructed in a cross or cruciform plan, typical of the Romanesque period. The octagonal “crossing tower” rises in the middle where the four arms, or wings, meet. In the basement, the central pillar and vaulted arch carry the entire building’s weight to the outer walls. This unique arch design spreads the weight of the building evenly.

The prominent bands of small arches, known as Lombard bands, encircle much of the exterior of the building and is most noticeable in the octagonal tower where the windows are set within the recurring arches. It is also seen in the front entryway where the arches have been adorned with the fleur-de-lis and Tudor rose relief ornamentation. The use of decorative arches within receding arches is another feature of the Romanesque style.

The interior of the building is light and bare, with minimal ornamentation. Originally, barrel-vaulted cells lined the east and west wings of the ground and second floors. In total, the Gaol contained twenty-four cells, plus eight larger holding rooms meant to house twenty-eight males and five females. Male prisoners were mainly housed in the lower levels of the jail, while women were housed in cells upstairs. The men’s cells were approximately 8’ by 10’ and included a bed and toiletry items. On the second floor the women’s holding cell (located behind the large window above the main door) could hold up to five women who were separated by chicken wire and not cell walls. In 1956, a library was erected which housed over two hundred donated books. Space was also made available for religious services held each Sunday afternoon.

A Gaol yard was constructed for the purpose of allowing prisoners to exercise in the open air. A section of the yard was used for growing vegetables to supply the prisoners’ needs and to save considerable money. It was expected that prisoners would tend to the garden. The Gaol yard is also where the gallows were set up when most of the hangings occurred.

In spring 2019, work began to restore the original chimneys and two bartizans (wall mounted overhanging turrets) that were removed in 1954. The restoration project was made possible thanks to a generous financial contribution bequeathed by former teacher and architectural enthusiast, Bruce Flowers and included the creation of over 1,000 handmade bricks.

Although there have been a number of changes related to heating, water services, sewage, etc. to the Gaol over the years, the outside of the building, for the most part, retains its original style. Recognized by the National Inventory of Historic Buildings, the Old Gaol is regarded as an architecturally important building in Canada.