Tony Hanson and his daughter, Amelia, 5, stood in line Saturday for the opening run of the Casco Bay Eye.

Nicknamed after the London Eye, one of the world’s tallest Ferris wheels at 443 feet, the much shorter Casco Bay Eye at 90 feet still offered sweeping views of Casco Bay and Commercial Street.

“This was first on the list,” said Hanson, of Westbrook.

Hanson and his family were among the throngs milling around Portland’s waterfront for day two of the Old Port Festival. This year, the 41-year-old festival was expanded from one day to three days.

Saturday’s activities centered on the city’s working waterfront, organized by the Growing Portland collaborative, an economic development group formed by the Portland Regional Chamber of Commerce and Portland city government.

“We are trying to figure out ways to grow our marine economy,” said John Spritz, the collaborative’s manager.

There were self-guided tours of the wharves and piers, informational displays and open houses at some of the working waterfront’s maritime businesses. Festival-goers said the event gave them a chance to see parts of the city they don’t normally visit.

“It’s good to go around and visit local stores,” said Tyler Plante of Portland.

Plante, his sister, Alexandra Plante, and their friend Brian Marshall were participating in the festival’s scavenger hunt, setting out with more than 100 others from Monument Square on a race to complete challenges at assorted downtown businesses to win prizes, including tickets to a sky box at a Sea Dogs baseball game.

Andrew Jones, his wife, Becky, and daughter, Mya, 9, said the festival was a must-see activity in their first year of living in Maine after moving from Chicago to Scarborough.

“This is the best place in the world,” said Mya, who sported neon orange crab earrings.

The Gulf of Maine Research Institute’s Sustainable Seafood Initiative table on Commercial Street offered free skewers of dogfish grilled by Charlie Bryon, owner of the Salt Exchange restaurant.

“People are always a little suspicious when you give away food on the street,” Bryon said.

The Gulf of Maine Research Institute is working with the seafood industry to create demand for dogfish, which is hard to find in local seafood markets at this point. Terry Harriman, chief executive officer of North Atlantic Inc., which processes dogfish, said Bowdoin College and Yale and Cornell universities have become big customers of the fish.

Festival-goers gave thumbs up to the meaty white fillets.

“I want to get more dogfish. I want to freeze it for the winter,” said Mary Jane Matt of Plainville, Connecticut.

The festival continues from 11 a.m. to 5 p.m. Sunday with the traditional parade, amusement rides, crafts and live music in the Old Port.