Labour is New Zealand's oldest political party - started 100 years ago on July 7, 1916.
Members of its Whanganui branch met to mark the centenary on Thursday this week, with drinks at the Grand Hotel.
The hotel has been the venue for many a party election meeting. Branch deputy chairman Bob Dempsey said it had "good vibe" for members.
The celebrations went "very well", with just over 30 people attending, he said.
"Several people brought various memorabilia from the party's history, things from way back like news paper articles from 90 years ago."
For Mr Dempsey, the highlight of the night was listening to people reminisce and talk about the reasons they joined the party.
Whanganui has a strong Labour tradition, branch chairman Craig Paynter said.
Its branch membership has grown in the last few years, and new members are always welcome.
The Whanganui Electorate also has a Labour Party branch based in Stratford and Eltham.
Whanganui has had four Labour MPs, the most well-known being Russell Marshall. He was in Parliament from 1972-90, was a successful education minister, took a hand in foreign affairs and was New Zealand's High Commissioner in London from 2002-05.
The branch is now in the process of identifying potential candidates for the 2017 election, since previous candidate Hamish McDouall has said he will contest the mayoralty instead.
The Labour Party's most famous leaders have been Michael Joseph Savage, Norman Kirk, David Lange and Helen Clark.
Among its achievements are the 40-hour working week, building thousands of state houses, the 1939 act that created a welfare state with free health care and benefits, the 1975 Treaty of Waitangi Act and the 1987 nuclear-free New Zealand policy.