From the Governor of Svalbard:
Celebrating the 100th anniversary of the Svalbard Act on 14 August
And:We are celebrating that August 14th marks 100 years since Svalbard became part of the Kingdom of Norway. HRH Crown Prince Haakon, Prime Minister Støre and Minister of Justice Aas-Hansen will attend the celebration.
The incorporation of Svalbard as part of the Kingdom of Norway occurred through the entry into force of the Svalbard Act on 14 August 1925. Since then, Svalbard, which in area constitutes an area as large as Norway south of Dovre, has been part of what, according to Section 1 of the Constitution, is a "free, independent, indivisible and inalienable kingdom."
This will be celebrated in Longyearbyen on Thursday, 14 August 2025. HRH Crown Prince Haakon, Prime Minister Jonas Gahr Støre and Minister of Justice Astrid Aas-Hansen will participate in parts of the program.
The celebration will begin with a wreath-laying ceremony at the Sverdrup memorial stone at Huset and at the monument to fallen miners.
At 11:00 there will be an anniversary service in Svalbard Church, and at 11:50 there will be a ceremony at the monument on Skjæringa and a flag raising at 12:00.
At 13:30 there will be a public celebration and entertainment on the square in Longyearbyen. The day will end with a festive performance in Longyearbyen Cultural Centre at 17:00....
Program for anniversary celebration 14 August
From The Economist, August 11:
Barentsburg, A Russian-run company town in Arctic Norway, could become a geopolitical headache.
A bust of Lenin glowers over the square in Barentsburg. Public signs are in Cyrillic script; murals and banners celebrate Russian scientists and artists. Russia’s tricolour flaps from buildings beside ones for Arktikugol, a Russian mining company. A Russian outfit provides the phone service, and shops sell Russian gherkins, tinned fish and fizzy drinks. Russian scientific institutes dot the town. Outside one, bathed in midnight sunshine, two geologists explain they are on their annual research visit from St Petersburg.You might think this settlement is part of Russia. It’s not. Barentsburg is a geopolitical quirk: a Russian company town squatting on Svalbard, an Arctic archipelago that belongs to Norway. The NATO country has undisputed control, thanks to a treaty that came into force on August 14th 1925. As The Economist went to press, Jonas Store, Norway’s prime minister, was set to preside over a 100th anniversary ceremony in Longyearbyen, Svalbard’s capital. But the treaty also grants nationals and companies from other countries broad rights to exploit resources there, notably by mining coal. Russians have done so since the 1930s.Some western intelligence officials fear the arrangement gives Russia an opening to cause trouble. Norway’s intelligence chief, Admiral Nils Andreas Stensonses, warned in June that lately the Arctic “gets more attention” from Russia, in part because the Baltic Sea has become unfriendly waters since it invaded Ukraine. Three years ago Russian trawlers sabotaged a communications cable that runs hundreds of kilometres to the Norwegian mainland. The next year Vladimir Putin’s administration designated Norway as unfriendly. In March Russia accused Norway of breaching the treaty with its military activity in Svalbard....

I'm not entirely sure what the Russian play is here. It might be as straightforward as securing access to the Atlantic for Russia's Arctic-based submarines:
Going back to December's Geopolitics: "Moscow aims to enhance presence in Svalbard as part of hybrid-strategy, expert warns":
And September 2024's Meanwhile, In The Arctic: "Svalbard-research becomes more important for China, professor says".