This week's festivities included a parade, carnival, and canoe race.
Today Senator Collins helped seal a time capsule commemorating the occasion.
Along with momentos from the town, Collins added a special senate coin and an American flag to the capsule.
She says she couldn't miss the chance to help a town with such a storied history mark its 200th birthday.
"It's an interesting community that has had manufacturing, farming, forest products industry. It's a very diverse community in its industrial and economic base. Most of all it's a community where people really pull together, and I think the response to this bicentennial celebration illustrates how much the residents care about the community," said Collins.
The time capsule will be opened at Newport's tri-centennial in 2114.