The Saint Vitus Cathedral located in Prague Castle was commissioned by Bohemian kings and Holy Roman Emperors such as Charles IV and Premysl Otakar II in the 14th century. The Gothic style cathedral features 21 chapels including the Chapel of Saint Ludmila and was constructed over several centuries under master builders like Matyas from Arras and his successor Peter Parler, utilizing vertical emphasis with arched windows and a strong supporting system between narrow walls.