The cave is located on Aghios Georgios hill and is one of the most remarkable sights of the city. It was discovered by accident in 1925, by lumber-jack Georgio Pavlidi when he opened its entrance while cutting trees. A mysterious area extends over 500 m with two floors which are more than 1000 sq m each and full of stalagmites and stalactites. Kilkis cave has a very distinctive formation with six broad halls where scientists discovered fossils of animal bones such as hyenas, horses, deer and rodents. Visitors should go there only if they are accompanied by an expert guide. According to the research of Czech doctors, the cave has therapeutic advantages perfect for asthma and other pneumonic or dermal conditions.