Holy Fifteen Tiberiopolis Martyrs is an archaeological site located in the city of Strumica. Tiberiopolis used to be the name of the city and the Holy Fifteen Tiberiopolis Martyrs are Christian saints living in the 4th century. They lost their lives in the name of the Christian beliefs and they were executed. During the excavations, the archeologist discovered a three-nave basilica with marble floors and mosaic decorations, like most of the early Christian tombs painted with crosses and reveals the truth about the events of the 4th century on this place.
In 7th century, the city was destroyed by the Avars and the tombs were buried. In 9th century, many churches were built and renewed and over the tombs of the martyrs was built a cross-shaped church that consists in one of the oldest fresco paintings in Macedonia. During the Ottoman period the church was destroyed. In 1921, the revival of the cult was marked by building a small chapel, but the new church was completed in 1974. Today, the holy martyrs are celebrated by the Macedonian Orthodox Church on 11th December.