The world's largest rubber duck and a Viking ship will be among the "grandest ships of yore" that will be on display as thousands head into Duluth this weekend for the Festival of Sail.

The festival, commonly known as the tall ships festival, is expected to draw the year's largest number of visitors to Duluth for a single event, organizers say. Starting Sunday with a boat parade at 9 a.m. and concluding on Tuesday evening, the festival grounds extend from the Bayfront Festival Park to the Aerial Lift Bridge. Events include boat tours, performers, and numerous food and drink vendors.

In past years, the festival typically ran over an entire weekend — instead of starting on Sunday. Competition from other big events happening in the area, as well as a desire to spread the crowds over several days, led to the schedule change, said Ryan Whaley, public relations director for the festival.

When it was over the entire weekend, people mainly attended on Saturdays, Whaley said. Now, they hope the crowds are better spaced throughout the three days.

“It kind of balances things out more (and) allows more people to get on the ships and see more,” he said.

Vehicle and marine traffic will likely experience delays on Sunday, as the festival is expected to bring the year’s largest number of people attending a single event.

Whaley estimates that around 100,000 people could attend the festival over the three-day span.

“Right now, ticket sales are indicating that we're going to have big crowds, but just like anything else … you have a lot of people buy their tickets the day of,” he said.

The last time the festival was held in the Twin Ports was in 2016. It returns to Duluth because both the attendees and ship crews love the festival.

“It’s always a great audience response here — folks just love this event. But also the ships like to come here,” Whaley said. “They like to go to the Great Lakes.”

Ships include the U.S. Brig Niagara, S/V Denis Sullivan and the former U.S. Coast Guard Cutter Sundew. The 42-foot Leif Erikson, a replica Viking ship that's been in storage in Duluth since 2013, will also be on display in Canal Park for the festival.

Whaley, who's also a business partner of the festival, said he's most excited for the world's largest duck. "It's a labor of love, because it takes so much to put that thing up," he said.