Lublin castle was founded in the . It is one of the oldest royal residences in the country. Now it is the iconic symbol of the city. In the castle’s courtyard, you will find the Chapel of Holy Trinity. It was added to the Castle in 14th century – during the reign of Casimir III the Great – one of the most powerful Polish kings. The chapel’s coping is decorated with Byzantine-style frescoes influenced by the Eastern Orthodox church.