Church of the Assumption, Baroque pilgrimage church in Chlum u Třeboně, Czech Republic

The Church of the Assumption is a High Baroque pilgrimage church in Chlum u Třeboně, built between 1737 and 1745 on a cross-shaped plan with a central dome. Its main tower and four small corner turrets are said to symbolize the name of the Fünfkirchen counts, meaning 'Five Churches'. In 1804 the church was extended westward with a three-nave hall and a music gallery.

Baron Jan František z Fünfkirchenu founded the church as a votive offering after he survived being buried under masonry on 31 July 1737 while inspecting a shooting range on the Hejtman pond dam; the mason master died. Built 1737–1745 on a cross plan, it was consecrated on 25 November 1745. In 1804 his grandson lengthened it westward with a three-nave hall and music gallery. A fire on 25 March 2024 damaged the roof and organ.

Pilgrimages are held here on 15 August, the Assumption, or the nearest Sunday. The high altar is modelled on the 1727 silver altar of the Mariazell chapel, and above the tabernacle stands a clothed Baroque copy of the Mariazell Madonna, dressed in embroidered robes. The vault under the music gallery carries a 1945 fresco of a procession led by parish priest Jan Kubiska, painted by Jiří Jelínek with real Chlum inhabitants.

The church stands on a slight rise about 500 metres from Chlum u Třeboně Castle, reached by a two-armed staircase lined with statues of saints. From the Hejtman pond side, the dome and the staircase are the clearest points of orientation. Pilgrimages are held on 15 August or the nearest Sunday.

In the crypt beneath the church lie the founder Jan František z Fünfkirchenu, his wife Anna Kateřina and Count Eduard ze Stadionu. It was here that the children of Franz Ferdinand d'Este and Sophie Hohenberg learned of their parents' assassination in Sarajevo in 1914.