In the old core of Sremski Karlovac is Ecology Center Radulovački, energy-efficient accommodation facility which primarily serves to educate citizens. Ecological Center Radulovački is a favorite destination of various groups that carry out education, and individuals who want to explore the city and its countryside. The center consists of two buildings. The first dates back to the eighteenth century and is protected as a cultural and historical monument, and the other, more modern, is one of the first examples of energy efficient buildings in Serbia. More modern edifice is built according to the principles of sustainable architecture, uses solar and geothermal energy, giving visitors an example of good practice.