overview opening hours The Portheimka Summerhouse was built in 1728 by Kilian Ignaz Dientzenhofer for his family as a summer residence. The décor is largely attributable to Vavřinec Reiner, one of the leading Czech painters of the High Baroque period. He painted the ceiling fresco representing the Bacchus Festival in the dome of the oval marble hall on the first floor, the most magnificent space in the Portheimka residence. The summerhouse is administered by the Prague 5 City Ward, which organises short-term exhibitions in the small gallery on the first floor. opening hours january—december mon closed tue, wed, thu, fri, sat, sun 13:00—18:00 more about opening hours Source: www.portheimka.cz opening hours january—december mon closed tue, wed, thu, fri, sat, sun 13:00—18:00