The Black Plague swept Vienna in 1713, and Emperor Charles VI vowed to build this church if the disease abated. Construction on Karlskirche, dedicated to St. Charles Borromeo, began in 1716. The master of the baroque, Johann Bernard Fischer von Erlach, did the original work from 1716 to 1722; his son, Joseph Emanuel, completed it between 1723 and 1737. The lavishly decorated interior stands as a testament to the father-and-son duo. J. M. Rottmayr painted many of the frescoes inside the church from 1725 to 1730.

The green copper dome is 72m (236 ft.) high, a dramatic landmark on the Viennese skyline. Two columns, spinoffs from Trajan's Column in Rome, flank the front of the church, which opens onto Karlsplatz. There's also a sculpture by Henry Moore in a little pool.