Visitors to the Prime Minister's Chancellery, open from 4pm until 2am local time, will be able to tour state reception rooms that have hosted President Volodymyr Zelensky of Ukraine, French President Emmanuel Macron and Canadian Prime Minister Mark Carney in recent months.
The programme includes an exhibition of diplomatic gifts and a display on protocol.
At Belweder Palace, the presidential residence, doors open from 5pm to 11pm.
Visitors can explore the formal state rooms and a reconstructed study of Marshal Józef Piłsudski, the early 20th-century statesman.
The Senate is marking the occasion with a tribute to Andrzej Wajda, the Oscar-winning film director who is one of the official patrons of 2026.
An exhibition prepared by the Manggha Museum in Kraków traces his career as an artist, senator and public figure, and a dedicated screening zone will show footage of Wajda at work.
At the Sejm, the lower house of parliament, a mosaic exhibition by students from the Warsaw Academy of Fine Arts will be accompanied by jazz performances and a candlelit string quartet recital.
Workshops run by the Chopin Institute are also planned.
All venues are free to enter, with visitors required to bring a valid identity document.
Polish Radio is also taking part in Museum Night, offering studio tours, meetings with journalists, concerts and access to areas not normally open to the public.
(ał)
Source: PAP, IAR