The Place d’Armes, formerly called 'Fief Pachirini,' was a fur trading site among the First Peoples. In 1648, Pachirini, an Anishinaabe chief, was granted this stretch of land located near the fort. In 1722, the land became home to a public market while continuing to host trade with Indigenous peoples, and by 1751, it was also used by the military for their maneuvers, which explains its current name, 'Place d’Armes' (Square of Arms).

The Manoir de Tonnancour, built in 1723 by René Godefroy de Tonnancour, has served many purposes, including as a residence, store, and officers' barracks during the English regime. Later, it functioned as a rectory and bishopric before becoming a primary school. It is one of the oldest houses in Trois-Rivières. Since 1972, the Galerie d’art du Parc has held around ten exhibitions and artistic events annually, showcasing the diversity of contemporary art in its various forms.