Thousands of New Zealanders watched indigenous Maori dancers twirl white "poi" balls in a blur of motion and take to traditional canoes, or waka, in the picturesque Bay of Islands as the country celebrated its 175th anniversary over a three-day weekend.

Waitangi Day, as the national day is called, is marked by protests, music, celebration and reflection.

It commemorates the signing of New Zealand's founding document, the Treaty of Waitangi. The agreement between British royalty and Maori chiefs gave Britain sovereignty over the fledgling nation. It also guaranteed Maori certain rights over their traditional lands and fisheries.

The contents and meaning of the treaty have been hotly debated since it was signed on Feb. 6, 1840, including whether Maori ever ceded sovereignty. Different versions in Maori and English meant different things. For the past 25 years, New Zealand's government has been compensating Maori tribes that have brought grievances under the provisions of the treaty.

"I think it's a day to reflect," said Te Ururoa Flavell, the Minister of Maori Development. "Reflect on where we are as a nation in 2015. Reflect on the dreams and aspirations of our people 175 years ago."

He said the treaty is not just about Maori but is about the relationship between all New Zealanders.

Each year, the tiny town of Waitangi in the far north of the country hosts a popular festival on the grounds where the treaty was signed. Some groups perform traditional Maori dance, or kapa haka, while others paddle. Festival goers are treated to the aroma of fried bread and barbecued seafood delicacies like mussel fritters.

Protests are a feature of Waitangi Day. However, this year's protests did not cause any disruptions. The country's politicians have been targeted in the past, but Prime Minister John Key was able to walk onto the Te Tii Marae, a revered Maori gathering place, and talk in a meeting house.

Key said statistics show that many aspects of life for Maori are improving, whether the measure is longevity or school participation. He said the financial settlements made to tribes were noted by other nations that last year voted in favor of New Zealand taking a temporary seat on the U.N. Security Council.

"Quite a lot of countries who had studied New Zealand congratulated us on our indigenous rights and, as part of that, what we were doing around treaty settlements," Key said. "I think for some countries it was one of the reasons they voted for us."