Renovation of the Rotunda of the Finding of the Holy Cross in Prague 1, a project carried out by the capital city, revealed an unexpected and very valuable find - very well preserved spongilite sheets of the original roofing. Research is currently underway and upon its completion, the original material will be eventually left in place and covered with new roofing. The significance of the discovery lies mainly in new insights into historical construction practices and the use of construction materials.

“The discovery is a wonderful proof that Prague has not yet divulged all its secrets. At the same time, I am pleased that the builders were so sensitive in the restoration of the rotunda that conservationists are able to explore the historic structure,” says City Councilor Jan Chabr who is in charge of the municipal asset management.

The renovation works should be completed this autumn and the total cost is expected to reach CZK 6.3 million including VAT.

The Chapel of the Finding of the Holy Cross, located at the corner of Konviktská and Karoliny Světlé streets in Prague 1, is one of the oldest preserved church buildings in the capital city. The Romanesque building dates back to the first half of the 12th century.