Grosse Isle

Grosse Isle is a historic quarantine station located in the St. Lawrence River, featuring white hospital buildings, a church, and a Celtic cross positioned on a hillside. The island preserves structures and grounds from when ships arrived with passengers and medical staff worked to inspect and monitor those coming ashore.

The station was established in 1832 and operated for over a century as an arrival point for people coming to Canada. During the famine years, it became the primary gateway where hundreds of thousands passed through before continuing to their destinations.

The site holds deep meaning for people tracing Irish heritage, as it marks where so many arrived seeking refuge during the famine crisis. Walking through the grounds, you encounter memorials and burial sites that speak to this shared family history.

The island is only accessible by boat from Berthier-sur-Mer or by small plane from Montmagny airport. You should plan your visit ahead of time since ferry and flight services vary with the season.

Medical staff used blue flags on ships to signal the presence of fever, a visual system that brought order to arrivals. This signaling method was one of the earliest standardized ways to manage the flow of incoming vessels in North America.

Location: Saint-Antoine-de-l'Isle-aux-Grues

Part of: Isle-aux-Grues archipelago

GPS coordinates: 47.03333,-70.66667

Latest update: December 7, 2025 20:25