Poland has a rich festival calendar spanning music, film, folk culture, and religious tradition. Summer is the busiest season.
Music
Open'er Festival (Gdynia, early July) is one of the biggest international music festivals in Central Europe, held at the Gdynia-Kosakowo Airport. The lineup is broad — rock, electronic, hip-hop, pop — and the setting is unusual. Tickets sell out well in advance.
Pol'and'Rock Festival (near Poznan, late July/early August) is a free outdoor festival organized by the Great Orchestra of Christmas Charity (WOŚP). It draws hundreds of thousands of people and has a genuinely communal atmosphere. No ticket price, but donations welcomed.
Warsaw Summer Jazz Days (Warsaw, July) brings international jazz acts to outdoor and indoor stages across the city.
Warsaw Autumn (Warsaw, September) is Poland's foremost contemporary classical music festival, founded in 1956. Not for every traveller, but serious music lovers will find it one of Europe's best.
Film
New Horizons International Film Festival (Wroclaw, late July) is Poland's most prestigious arthouse film festival, showing independent and international cinema over ten days.
Folk and Traditional
Lajkonik Pageant (Krakow, June — Thursday after Corpus Christi) is one of Krakow's most colourful traditions, featuring a costumed procession through the city streets from Zwierzyniec to the Market Square.
Battle of Grunwald Reenactment (near Olsztyn, mid-July) recreates the 1410 battle — one of the largest medieval battles in European history — with hundreds of participants in full armour. Genuinely spectacular.
Carnaval Sztukmistrzów (Lublin, late July) fills the city with street circus acts, acrobatics, and performance art for several days.
Religious
Poland is predominantly Catholic, and religious festivals are widely observed. Easter (Wielkanoc) is a major event — shops close, families gather, and traditions including Śmigus-Dyngus (water fights on Easter Monday) are taken seriously. Corpus Christi processions are elaborate in many towns. All Saints' Day (1 November) sees Poles visit cemeteries in large numbers, and the lit candles at night are genuinely moving.