There are three buildings on the site: the Old Stone Ermatinger House, the Clerg log cabin and the Heritage Discovery Centre. The Ermatinger and Clerg Houses are considered the oldest buildings northwest of Toronto. Completed in 2014, the Heritage Discovery Centre was designed to provide additional space for interpretation and programming of the historic site.
The Old Stone Ermatinger House is the original building on this site, built between 1814 and 1823 and is considered one of the oldest surviving houses in Northern Ontario. It was built by former North West Company fur trader Charles Oakes Ermatinger, who lived in this house with his wife and children. He resided there until 1828, when he cut his ties in Sault Ste. Marie after the death of his brother Frederick William. It was recognized as a National Historic Landmark in 1957.
The house is built of native stone and wood and faces St. Mary’s River Street. It was considered large for its time and was an imposing landmark at the time of construction. After the Ermatinger family left, the house was used by its subsequent residents as a mission, hotel, tavern, courthouse, post office, dance hall, tea house and dwelling house. The house was purchased by the city of Sault Ste. Marie in 1965 and was restored before opening the house museum to the public.
Sault Ste. Historian Marie McNeice began researching the history of the Old Ermatinger Stone House and the Ermatinger family in 1956. This work eventually led to the publication of a book entitled The Ermatinger Family in Sault Ste. Marie, posthumously published by McNeice’s daughter.
The Clerg Blockhouse was originally a powder cellar in the Northwestern Company trading post prior to the merger of the Northwestern Company and the Hudson’s Bay Company. When the last remaining factor at the post retired in 1867, the site fell into disuse until only the foundation building of the powder depot remained. American industrialist F.H. Clerg then purchased the property and began the process of converting it from a powder depot into living space. He lived in the blockhouse from 1894 to 1902.
In 1979, the blockhouse was recognized as a local historic landmark by the town of Sault Ste. Marie, Ontario. In 1995, when the St. Mary’s Paper Mill planned a development that would have jeopardized the location and structure of the blockhouse. In 1996, the building was purchased by the city of Sault Ste. Marie and moved from the original St. Mary’s Paper Mill site to the site of the old Ermatinger stone house.