PORTSMOUTH, N.H. — New Hampshire and Maine celebrated the opening of a new bridge Thursday that has become a steel symbol of their past cooperation and their commitment to future commerce.

The $81.4 million Memorial Bridge between Portsmouth and Kittery, Maine, replaces one that was built in 1923 and closed two years ago.

As she did 90 years ago at age 5, former Portsmouth mayor Eileen Foley did the ribbon-cutting honors, riding across the bridge in a golf cart with a bouquet of flowers on her lap. The crowd cheered as she cut the ribbon, then sang “God Bless America.”

New Hampshire Gov. Maggie Hassan noted that the bridge includes state-of-the-art technology to meet the needs of modern commerce and travel, yet echoes the look and feel of the original.

“The new bridge reminds us all of the historic connection between Maine and New Hampshire as well as our shared economic future,” she said. “The new Memorial Bridge will once again link the downtown areas of Portsmouth, New Hampshire, and Kittery, Maine, and support the business, social, tourism and cultural activities of both communities and the entire seacoast region.”

After the ceremony, hundreds of people swarmed over the bridge, the only one of the three over the Piscataqua River that is open to pedestrian and bicycle traffic. Joanne Bisson, who lives just over the bridge in Kittery, said she was thrilled to cross it once again.

“It’s a vital link. We walk in and enjoy Portsmouth,” she said. “It’s just community.”

Hassan and other speakers at the ceremony praised the congressional delegations from both states for securing a $20 million federal grant for the project. They also thanked the local businesses that supported it and the construction workers who spent months building the new bridge.

U.S. Sen. Susan Collins, R-Maine, noted that Maine is the only state that borders just one other state.

“Our one and only U.S. neighbor is New Hampshire, but we share much more than just the border. We share a history rooted in independence and a culture built on hard work and self-reliance,” she said. “We are here today because we also share an economy and a commitment to the future.”

Just as the two states worked together to save the Portsmouth Naval Shipyard from closure, they rallied to replace the bridge, Collins said.

“We grew up together, and we stand together,” she said.

Before the speeches, two police officers on motorcycles led a procession from Kittery that included a color guard, musicians, antique cars and state, local and federal officials. Portsmouth Officer Chris Kiberd said later “it was a pretty cool opportunity” to be part of history.

“I felt like I was at my wedding with so many people taking pictures of me,” he said.