Brno, Czech Republic Brno is the second largest city in the Czech Republic by population and area, the largest Moravian city, and the historical capital city of the Margraviate of Moravia. There are many museums, theatres and other cultural institutions. Brno is also a vibrant university city with about 90,000 students, and a number of festivals and other cultural events. Brno has hundreds of historical sights, including one designated a World Heritage Site by UNESCO