MICHIGAN CITY, Ind. (AP) — A museum in Michigan City is planning a memorial for 844 people who died more than a century ago when a ship capsized on the Chicago River.

The SS Eastland was loaded with employees from Chicago’s Western Electric Company when it capsized before embarking on a planned trek across Lake Michigan for a company picnic in Michigan City.

The July 24, 1915, disaster killed 844 people, making it the deadliest shipwreck on the Great Lakes.

The (Northwest Indiana) Times reports that the Old Lighthouse Museum in Michigan City will hold a memorial ceremony July 27 for the Eastland’s long-ago victims.

Speakers will recount the tragedy and lay a wreath on Trail Creek, where the Eastland would have docked for the planned picnic.