Holy Trinity Column on main square in Tvrda, the old citadel in Osijek, Croatia (June 2014). Osijek's Tvrda was built in the form of an enormous and elaborate star-shaped fort with eight bastions, during the early 18th century. The elegant Baroque buildings in the interior form the most extensive and best-preserved ensemble of Baroque architecture in Croatia. Osijek's Tvrda has been submitted for consideration to the UNESCO World Heritage List. © Rudolf Abraham