Kremer Karol was an architect, restorer and builder. He was born in 1812 in Krakow. He studied at the Jagiellonian University, later became a builder and then director of construction. He married Maria Grabowska. Karol Estreicher was his brother-in-law. The main contribution of Karol Kremer was the introduction of modern fire prevention methods in construction. The reason for this was the huge fire of Krakow in 1850, which burned many valuable buildings. Kremer rebuilt the burned Dominican and Franciscan churches, restored the famous tower of St. Mary’s Basilica, and contributed to a thorough renovation of the Collegium Iuridicum, Collegium Maius, Barbican and St. Florian’s Gate.