This old part with houses from the National Renaissance period (18th-19th century), is an imposing open-air museum situated on the three hills of the ancient Trimontium. It was only during the Renaissance Period that Plovdiv regained its glorious name of a large economic and cultural center. Almost all of the most interesting history-related sights are within the old-town area: cult, residential and public housing, archeological monuments and museums, narrow cobble-paved streets. The most famous houses are: the House of Argir Koyumdjiouglu (presently hosts the Ethnographic Museum), the House of Georgi Mavridi, where the French poet Lamartine lived in 1833, the House of Dimitar Georgiadi, now turned into a Museum of Bulgarian Renaissance, Balabanova House, etc.